Can pneumonia cause empyema (empyema is a collection of pus in the pleural space)?

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Last updated: March 31, 2025 • View editorial policy

From the Guidelines

Yes, pneumonia can cause empyema, a serious complication where pus collects in the pleural space between the lung and chest wall, as evidenced by a patient with a 3-week history of pneumonia developing a loculated pleural collection with overlying pleural thickening (empyema) despite a full course of broad-spectrum antibiotics 1.

Causes and Risk Factors

Pneumonia can lead to empyema when bacteria from the pneumonia infection spread to the pleural space. The most common bacteria causing empyema include Streptococcus pneumoniae, Staphylococcus aureus, and anaerobic bacteria. Empyema typically develops when pneumonia is left untreated or inadequately treated.

Symptoms and Diagnosis

Symptoms of empyema include persistent fever, chest pain, shortness of breath, and cough. Diagnosis often involves imaging studies like CT scans, which can show loculated pleural collections and pleural thickening, as seen in the case of a patient with pneumonia who developed empyema despite antibiotic treatment 1.

Treatment and Management

Treatment usually involves antibiotics targeted at the causative organism, often including combinations like ceftriaxone plus metronidazole or piperacillin-tazobactam, typically for 2-6 weeks depending on severity 2. Additionally, drainage of the infected fluid is necessary, either through chest tube placement or surgical intervention in more severe cases. Guidelines suggest that all patients should receive antibiotics as soon as pleural infection is identified, and the choice of antibiotics should be guided by bacterial culture results when possible 2.

Prevention and Importance of Early Recognition

Early recognition and treatment of pneumonia can help prevent this serious complication, so seeking medical attention promptly for symptoms of respiratory infection is important, especially if symptoms worsen or persist despite initial treatment. The management of pleural infection, including empyema, involves a combination of antibiotic therapy and drainage of the infected fluid, with the goal of reducing morbidity and mortality, as well as healthcare costs 3.

From the Research

Pneumonia and Empyema Relationship

  • Pneumonia can lead to complications such as lung abscess and empyema, as discussed in the study 4.
  • Empyema is a type of pleural infection that can occur as a result of pneumonia, with the pathogens responsible for pleural infection differing from those in pneumonia 5.
  • Parapneumonic effusions, which can progress to empyema, occur in 20 to 40% of patients hospitalized with pneumonia, and are associated with increased morbidity and mortality 6.

Pathophysiology of Empyema Development

  • The development of parapneumonic effusions and empyema is influenced by factors such as patient comorbidities, bacteriologic virulence features, and the cascade of inflammatory events in the lungs and pleural space 7.
  • The evolution of parapneumonic effusions can be divided into three progressive stages: exudative, fibrinopurulent, and organizing, which can help categorize effusions and evaluate the risk of a complicated course requiring intervention 7.

Clinical Implications

  • The management of parapneumonic effusions and empyema requires proper antibiotic selection, pleural fluid drainage, and consideration of surgical referral in patients who fail to respond to standard medical management 5.
  • Therapeutic thoracentesis and chest tube insertion may be necessary for patients with pneumonia and a parapneumonic effusion, with video-assisted thoracoscopic surgery and decortication considered for loculated effusions 6.

References

Guideline

acr appropriateness criteria® radiologic management of infected fluid collections.

Journal of the American College of Radiology, 2020

Research

Respiratory infections: pneumonia, lung abscess, and empyema.

Seminars in pediatric surgery, 2008

Research

Management of parapneumonic effusions and empyema.

Seminars in respiratory and critical care medicine, 2014

Research

Parapneumonic effusions and empyema.

Proceedings of the American Thoracic Society, 2006

Research

Pneumonia and empyema: causal, casual or unknown.

Journal of thoracic disease, 2015

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.