Pulmonary emphysema

Background

• A form of chronic obstructive pulmonary disease characterized by enlargement of the distal airspaces and destruction of airspace walls

Morphological Subtypes

Subtype	Description	Associations
Centrilobular emphysema	Most common, usually an upper lobe predominance	Closely associated with smoking
Panlobular emphysema	Involves entire acinus, more severe in lower lobes	alpha-1-antitrypsin deficiency or IV methylphenidate use, Swyer-James syndrome, obliterative bronchiolitis
Paraseptal emphysema	Occurs adjacent to the pleura and septal lines	Smoking, Marfan syndrome; risk of pneumothorax
Paracicatricial emphysema	Occurs adjacent to areas of scarring	Silicosis, granulomatous lung disease, tuberculosis, pneumonia, pulmonary embolismcausing infarct

Risk Factors

• Tobacco smoking (90% of cases)
• Alpha-1-antitrypsin deficiency
• Stimulant use disorder with injected methylphenidate ("Ritalin lung")

Clinical Manifestations

• Dyspnea
• Decreased breath sounds, lung hyperinflation
• Often moderate to severe airflow obstruction