Question

Empyema necessitatis is defined as so when

• A. Pleural empyema is under pressure
• B. Pleural empyema has ruptured into the bronchus
• C. Pleural empyema has ruptured into the pericardium
• D. Pleural empyema is showing extension to the subcutaneous tissue

Hint:

The word necessitatis points to pus tracking outward through the chest wall.

Answer 1

The Correct Option is D

This question is about the exact meaning of empyema necessitatis, a term for one particular way a chronic pleural empyema can spread.

1. Pleural empyema is under pressure: Pressure inside the pleural space does not tell us where the pus has gone, so this alone does not define the term.
2. Pleural empyema has ruptured into the bronchus: This describes a bronchopleural fistula, a separate and different complication from empyema necessitatis.
3. Pleural empyema has ruptured into the pericardium: This is not the classic pathway used to define either bronchopleural fistula or empyema necessitatis.
4. Pleural empyema is showing extension to the subcutaneous tissue: This matches the definition exactly, pus eroding outward through the chest wall to point under the skin, classically from a tuberculous or actinomycotic empyema.

Only the option describing pus tracking through the chest wall into the subcutaneous tissue matches the true meaning of the term.

Let's summarize:

• Empyema necessitatis: pus tracks outward through the chest wall to point under the skin.
• Bronchopleural fistula: pus ruptures inward into a bronchus, a different complication entirely.

So empyema necessitatis is defined by extension of the pus to the subcutaneous tissue.