Parapneumonic effusion

Dr Henry Knipe and Dr Tony Chen et al.

Parapneumonic effusion refers to an exudative pleural effusion associated with pulmonary infection.

Approximately 40% of patients who are hospitalized for pneumonia develop a parapneumonic effusion 3.

Fluid leaks into the pleural space due to increased permeability of the visceral pleura adjacent to the infected lung. Bacterial cases of pneumonia are a more common cause of parapneumonic effusions than viral cases of pneumonia 3

Similar findings to a simple pleural effusion 1:

Parapneumonic effusions often resolve with the treatment of the underlying pneumonia. However, ~7.5% of patients with parapneumonic pneumonia progress to a fibrinopurulent stage such as empyema 3

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Article information

rID: 30524
System: Chest
Tag: cases
Synonyms or Alternate Spellings:
  • Parapneumonic effusions
  • Parapneumonic effusion (PPE)

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Cases and figures

  • Case 1
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  • Case 2: pneumococclal pneumonia
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