Is empyema (empyema, a collection of pus in the pleural space) an infection?

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From the Guidelines

Empyema is indeed an infection, specifically a collection of pus in the pleural space, which represents one end of a spectrum of pleural infection. This condition is characterized by the macroscopic detection of purulent pleural fluid, as defined by the British Thoracic Society guideline for pleural disease 1. The term 'empyema' is often used to describe this condition, which can develop as a complication of pneumonia, chest trauma, surgery, or the spread of infection from elsewhere in the body.

Key Characteristics of Empyema

  • Collection of pus in the pleural space
  • Represents one end of a spectrum of pleural infection
  • Characterized by the macroscopic detection of purulent pleural fluid
  • Can develop as a complication of pneumonia, chest trauma, surgery, or the spread of infection from elsewhere in the body

According to the British Thoracic Society guideline, pleural infection is defined as bacterial entry and replication in the pleural space, and empyema is a manifestation of this infection 1. The guideline emphasizes the importance of prompt treatment, including antibiotics and drainage of the pus, to prevent serious complications such as lung abscess, sepsis, or chronic scarring of the pleural space.

Treatment of Empyema

  • Antibiotics to fight the infection
  • Drainage of the pus through chest tube placement or surgical intervention
  • Common antibiotics used include combinations like ceftriaxone plus metronidazole, or piperacillin-tazobactam, typically administered intravenously for 2-6 weeks depending on severity

While older guidelines, such as the 2003 BTS guidelines, provide additional information on the management of pleural infection, including the use of chest tube drainage and pleural fluid pH measurement 1, the most recent and highest-quality evidence supports the definition and treatment principles outlined in the 2023 British Thoracic Society guideline 1.

Importance of Recent Guidelines

  • The 2023 British Thoracic Society guideline provides the most recent and highest-quality evidence on the definition and treatment of empyema
  • This guideline should be prioritized in clinical decision-making over older guidelines, such as the 2003 BTS guidelines 1

From the Research

Definition and Causes of Empyema

  • Empyema is defined as pus in the thoracic cavity due to pleural space infection, with a multifactorial underlying cause 2.
  • The majority of empyema cases are post-bacterial pneumonia caused by tuberculosis or by infection following penetrating chest injuries or surgical procedures 2.
  • Empyema can also occur as a complication of pneumonia or lung abscess, and 15% to 30% of cases occur after thoracic surgery 3.

Infection and Antibiotic Therapy

  • Empyema is an infection of the pleural space, and antibiotic therapy is a crucial part of its management 2, 4, 3.
  • The initial choice of antibiotics depends on whether the empyema is community-acquired or nosocomial 4.
  • Single antibiotic agents that are likely to be active against the wide spectrum of potential pathogens include imipenem-cilastatin and ticarcillin-clavulanic acid 3.
  • Combinations of antibiotics should include an effective agent against anaerobic bacteria, coupled with an agent active against aerobic gram-positive cocci and gram-negative bacilli 3.

Management and Treatment

  • Treatment of empyema can be summarized as appropriate antibiotic therapy combined with medical or surgical pleural space drainage, management of any underlying factors, with further surgery indicated for chronic disease 2.
  • Early drainage with or without intrapleural fibrinolytics is usually required, and surgical decortication is needed in some cases 4.
  • Video-assisted thoracoscopic surgery (VATS) is a minimally invasive procedure that can be used to manage empyema, and it is preferred over open thoracotomy in many cases 4, 5.
  • The use of intrapleural fibrinolytics in managing complicated pleural effusions and empyema is still a topic of debate and controversy among clinicians 5.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Thoracic empyema: current opinions in medical and surgical management.

Current opinion in pulmonary medicine, 2010

Research

Antibiotic therapy of pleural empyema.

Seminars in respiratory infections, 1991

Research

Medical and Surgical Management of Empyema.

Seminars in respiratory and critical care medicine, 2019

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.

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