Empyema

An empyema is a collection of pus inside a space in the body where fluid naturally collects. The term is most often used to describe pleural empyema, which happens in the pleural cavity—the area around the lungs. Though it shares similarities with an abscess, empyema is a special term used by doctors in certain situations.

Empyema usually happens after an infection, most commonly pneumonia. It can also occur from other health problems that cause infected fluid to build up in a body cavity. This condition needs medical attention because it can affect a person’s health and recovery.

Classification

Empyema is when a build-up of pus happens inside parts of the body. It can occur in several places, such as the space around the lungs, called the pleural cavity, or inside the uterus, appendix, meninges, joints, and gallbladder. Each of these locations can have its own specific name for this condition.

Diagnosis

Doctors use special pictures of the chest, like chest X-rays or computed tomography (CT) scans, to see if there is any fluid in the space around the lungs. If they find fluid, they may use a needle to take some of it out for testing. This helps them know if the fluid is infected and what might be causing the problem. Blood tests can also show if there is an infection in the body by checking for certain cells, like an increased neutrophil count, or if there is bacteremia.

For cases where the infection might be near the brain, more detailed brain imaging like MRI is used. In these situations, doctors use special needles to collect fluid samples instead of a method called a lumbar puncture, because this method usually does not help find the cause of the infection, unlike in most cases of meningitis.