Lung abscess

Lung abscess is a rare disorder, most frequently seen as a complication following aspiration.

Etiology

• Aspiration
• Pneumonia
• Septic emboli (endocarditis)

Aspiration is the most common cause of lung abscess, accounting for 80% of cases. Abscesses are typically polymicrobial, having similar flora as the oral cavity.

Clinical features

Symptoms are similar as for pneumonia, with cough, sputum, dyspnoea, chest pain, and fever. However, symptoms typically progress over a longer period of time, like weeks or months.

Diagnosis and evaluation

X-ray or CT can show the abscess with a thick wall and inner air-fluid level. It must be differentiated from other diseases which can form cavitations, like tuberculosis. Sputum and blood cultures should be obtained to guide therapy.

Aspiration of the abscess is usually not necessary unless there is treatment failure. If performed, the fluid should be cultured.

Treatment

The main treatment is antibiotics. Drainage is performed if patients don’t improve on antibiotics. It can be performed percutaneously or transbronchially.