Lung abscess

Background

• Localized, suppurative necrotizing process occurring w/in the pulmonary parenchyma
• Takes 7-14d for aspiration PNA to develop into an abscess
• Microbiology
  • Community-acquired: anaerobes (bacteroides, fusobacterium)
  • Hospital-acquired: Staph, E coli, Klebsiella, pseudomonas, legionella

Causes

• Aspiration PNA
• Bacteremia from nonpulmonary infection
• Pulmonary infarction
• Infection as a result of penetrating chest trauma
• Primary and metastatic neoplasms
• Wegener's, sarcoidosis

Clinical Presentation

• Several weeks of cough, fever, pleuritic chest pain, wt loss, night sweats
  • Tachycardia, tachypnea, or fever may be absent

Differential Diagnosis

• Cavitary lesion w/ air-fluid level
• Infected bullae
• Pleural fluid collection with bronchopleural fistula
• Loop of bowel extending through diaphragmatic hernia

Diagnosis

• CXR
• Dense consolidation w/ air-fluid level inside of a thick-walled cavitary lesion
  • Air-fluid level indicates communicatio nof abscess cavity w/ a bronchiole

Treatment

• Medical management will successfully treat 70-90% of lung abscesses
  • Drainage occurs spontaneously from communication of cavity w/ tracheobronchial tree
  • Bronchoscopic drainage may result in seeding other parts of the lung
• Antibiotics
  • Clindamycin + 2nd or 3rd gen cephalosporin OR
  • Clindamycin + ampicillin/sulbactam

Complications

• Empyema
• Massive Hemoptysis
• Failure of cavity to resolve

Disposition

• Admit

See Also

• Empyema

Source

Tintinalli