From the Guidelines
Recurrent empyema is primarily caused by inadequate drainage of the initial empyema, persistent underlying lung infection, or the development of antibiotic resistance, as highlighted in the most recent guidelines 1. The most common scenario involves incomplete drainage of the pleural space during initial treatment, allowing infected fluid to remain and continue causing inflammation. Underlying conditions that predispose patients to recurrence include:
- Bronchiectasis, as discussed in the British Thoracic Society guideline for bronchiectasis in adults 1
- Lung abscess
- Tuberculosis
- Immunocompromising conditions such as diabetes, HIV, or use of immunosuppressive medications Anatomical factors like bronchopleural fistulas can also lead to recurrent empyema by allowing continuous contamination of the pleural space. Treatment typically requires a combination approach with:
- Appropriate antibiotics (often broad-spectrum initially, then targeted based on culture results) for 2-6 weeks, as recommended in the BTS guidelines for the management of pleural infection 1
- Thorough drainage procedures such as chest tube placement or video-assisted thoracoscopic surgery (VATS)
- Sometimes decortication to remove restrictive fibrous tissue Prevention of recurrence involves:
- Addressing the underlying cause
- Ensuring complete drainage of the initial empyema
- Appropriate antibiotic therapy
- Management of any comorbidities that might impair immune function or promote infection, as emphasized in the latest British Thoracic Society guideline for pleural disease 1.
From the Research
Causes of Recurrent Empyema
The causes of recurrent empyema can be attributed to several factors, including:
- Nonsepsis status prior to surgery, which increases the risk of recurrence [ 2 ]
- Nonperforming decortication, a surgical procedure that removes the thickened pleural membrane, can lead to recurrent empyema [ 2 ]
- Persistent pleural spaces, which can provide a conducive environment for bacterial growth and recurrence [ 2 ]
- Inadequate treatment of an empyema, which can result in the infected fluid dissecting into the chest wall [ 3 ]
- Contamination of the pleural space during tube insertion in patients with thoracostomy tubes [ 4 ]
Pathogenesis of Empyema
The pathogenesis of empyema can be attributed to various sources, including:
- Primary pneumonic sources, such as pneumonia or lung abscess [ 4 ]
- Intraabdominal sources of infection that seed the pleural space secondarily [ 4 ]
- Contamination of the pleural space during medical procedures, such as tube thoracostomy [ 4 ]
- Polymicrobial infections, which can involve multiple species of aerobic and anaerobic bacteria [ 5 ]
Bacteriology of Empyema
The bacteriology of empyema can vary depending on the underlying cause, but common pathogens include:
- Staphylococcus aureus, which is often isolated in empyema cases [ 2, 4 ]
- Acinetobacter baumannii, which is a common gram-negative pathogen [ 2 ]
- Streptococcus pneumoniae, which can cause empyema in the setting of pneumonia [ 4 ]
- Anaerobic bacteria, which can be present in up to 75% of empyema cases [ 5 ]