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Empyema is a collection of pus in the space between the lung and the inner surface of the chest wall (pleural space).



Empyema is usually caused by an infection that spreads from the lung. It leads to a buildup of pus in the pleural space.

There can be a pint or more of infected fluid. This fluid puts pressure on the lungs.

Risk factors include:

In rare cases, empyema can occur after thoracentesis. This is a procedure in which a needle is inserted through the chest wall to draw off fluid in the pleural space for medical diagnosis or treatment.


Symptoms of empyema may include any of the following:

Exams and Tests

The health care provider may note decreased breath sounds or an abnormal sound (friction rub) when listening to the chest with a stethoscope (auscultation).

Tests that may be ordered include:


The goal of treatment is to cure the infection. This involves the following:

  • Placing a tube in your chest to drain the pus
  • Giving you antibiotics to control the infection

If you have problems breathing, you may need surgery to help your lung expand properly.

Outlook (Prognosis)

When empyema complicates pneumonia, the risk of permanent lung damage and death goes up. Long-term treatment with antibiotics and drainage are needed.

In general, most people fully recover from empyema.

Possible Complications

Having empyema may lead to the following:

  • Pleural thickening
  • Reduced lung function

When to Contact a Medical Professional

Call your health care provider if you develop symptoms of empyema.


Prompt and effective treatment of lung infections may prevent some cases of empyema.

Alternative Names

Empyema - plural; Pyothorax; Pleurisy - purulent


Broaddus VC, Light RW. Pleural effusion. In: Broaddus VC, Mason RJ, Ernst JD, et al., eds. Murray and Nadel's Textbook of Respiratory Medicine. 6th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 79.

McCool FD. Diseases of the diaphragm, chest wall, pleura, and mediastinum. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 99.

Update Date 2/4/2015

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