Pyopneumothorax (also known as infected hydropneumothorax or empyemic hydropneumothorax) is a pleural collection of pus and air. It may be thought of a variant of a thoracic empyema with air containing components although the etiology may be different.

The patient usually presents with chest pain and fever. Cough and breathing difficulty may be present.

As with a hydropneumothorax, it has a range of causes:

Many causative organisms have been implicated including Mycobacterium tuberculosis, anaerobes, pyogenic and fungal.

An air-fluid level is noted. It may be loculated. Loss of silhouette with the dome of diaphragm may be seen. It may be difficult to differentiate a pyopneumothorax from non-infected hydropneumothorax. Presence of thick pleural lining strongly favors the former.

Fine internal echoes in the pleural collection strongly suggests infected fluid in appropriate clinical settings.

CT will clearly depict the location of the collection as well as thickening of pleura and underlying disease process (if any).

Large collections require intercostal drainage with antibiotics.

On imaging consider

  • non-infected hydropneumothorax (no pleural thickening)
  • peripheral lung abscess
  • previous empyema with iatrogenic introduction of air (e.g. drain insertion or diagnostic aspiration etc.)

Article information

rID: 29776
System: Chest
Section: Gamuts
Synonyms or Alternate Spellings:
  • Empyemic hydropneumothorax
  • Infected hydropneumothorax

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Cases and figures

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