Causes of pleurisy 

Pleurisy is inflammation of the pleura. It's usually caused by another condition, such as an infection, but sometimes no cause can be identified.

The pleura are two thin sheets of tissue that separate the lungs and ribcage. One is attached to the ribcage and the other is attached to the lungs.

Between the pleural sheets is a thin layer of liquid that lubricates the pleura, helping to reduce friction when you breathe in and out.

When there's inflammation, the surfaces of the two layers can become rough and the fluid can become sticky. This can cause the layers to rub together, resulting in pain and discomfort.


An infection is the most common cause of pleurisy. Any type of infection has the potential to spread to the pleura, but viral infections are usually responsible.

Viruses known to cause pleurisy include:

In some cases, pleurisy is caused by bacteria, such as:

Meticillin-resistant Staphylococcus aureus (MRSA) can cause pleurisy, especially in hospital patients. MRSA is a type of bacteria with a resistance to a number of commonly used antibiotics.

Other causes

Other possible causes of pleurisy include:

Autoimmune conditions, such as rheumatoid arthritis and lupus, are other possible causes of pleurisy. In these conditions, something goes wrong with the immune system (the body’s natural defence against infection and illness) and it begins to attack healthy tissue.

Page last reviewed: 28/01/2015

Next review due: 28/04/2017