Lung Abscess

Introduction

• Suppurative inflammation of lung tissue within normal parenchyma
  • result of autodigestion of tissue by inflammatory cells 
• Etiology
  • most often a result of
    • aspiration of oropharyngeal material
    • bronchial obstruction
      • e.g. cancer
    • sequela of bacterial pneumonia
  • common pathogens include Bacteroides, Peptostreptococcus, Fusobacterium 
  • more often seen in the right lung than the left
    • result of wider and straighter right mainstem bronchus
  • if multiple foci present the cause is most likely hematogenous spreading
• Risk factors
  • poor oral hygiene
  • impaired swallowing
  • immunosuppression
  • altered consciousness
• includes seizures, dementia and alcoholism  

Presentation

• Symptoms
  • fever, malaise
  • cough with sputum production
    • putrid or foul-smelling sputum
• weight loss, night sweats (subacute)

Evaluation

• CXR
  • infiltrates often with cavity in dependent portion of lung (depends on position)
    • air-fluid level in cavity 
• Labs
  • leukocytosis
• Sputum
  • may be helpful to identify etiologic organism though contamination is common