Empyema

An empyema is a collection of pus in a space in the body where fluid normally collects. The term is most often used for pleural empyema, which happens in the pleural cavity—the area around the lungs. Though it is similar to an abscess, empyema is a special word doctors use in certain cases.

Empyema usually happens after an infection, most often pneumonia. It can also start from other health problems that cause infected fluid to build up inside the body. This condition needs medical care because it can affect a person’s health and recovery.

Classification

Empyema is when pus builds up inside parts of the body. It can happen 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 places can have its own name for this condition.

Diagnosis

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

For cases where the infection might be close to the brain, doctors use more detailed brain imaging like MRI. In these cases, they 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.