• Primary (PSP)
  • No clinical lung disease
  • Typically occurs in tall thin males aged 15–30 years
  • Association with tobacco and cannabis smoking
  • Rare in patients aged over 40
• Secondary (SSP)
  • Airways disease (COPD, cystic fibrosis, acute severe asthma)
  • Infectious lung disease (Pneumocystis carinii (jiroveci) pneumonia; necrotizing pneumonia caused by anaerobic, Gram-negative bacteria or Staphylococcus aureus)
  • Interstitial lung disease (e.g. sarcoidosis)
  • Connective tissue disease (e.g. rheumatoid arthritis, Marfan syndrome)
  • Malignancy (bronchial carcinoma or sarcoma)
  • Thoracic endometriosis (‘catamenial’ pneumothorax)

Traumatic pneumothorax (due to penetrating or blunt chest trauma) should be managed by surgical team

Latrogenic pneumothorax

• Transthoracic needle aspiration
• Subclavian vein puncture
• Thoracentesis and lung biopsy
• Pericardiocentesis
• Barotrauma related to mechanical ventilation