Aetiology

Localised areas of emphysema may be caused by:

• congenital disorders
  
• compensatory changes:
  • lung collapse
  • scarring
  • resection
    
• partial bronchial occlusion:
  • foreign body
  • peribronchial lymphadenopathy
  • neoplasm
    
• in rare cases a unilateral emphysema may occur due to bronchiolitis before the age of 8 years
  
• smoking

Generalised:

• idiopathic / primary
  
• physiological (senile emphysema)
  
• familial:
  • alpha 1 anti-trypsin deficiency
  • lower lobes more severely affected
    
• associated with:
  • chronic bronchitis
  • chronic asthma
  • pneumoconiosis

Reference

1. NICE. Chronic obstructive pulmonary disease in over 16s: diagnosis and management. NICE guideline NG115. Published December 2018, last updated July 2019