Empyema

Overview

Empyema represents one of the oldest recognized thoracic conditions, with descriptions dating back to ancient Greek medicine. The term "empyema" comes from the Greek word meaning "suppuration," reflecting the purulent nature of the condition. Today, it affects approximately 65,000 people annually in the United States and United Kingdom combined, with incidence rates increasing in recent years despite advances in antibiotic therapy.

The development of empyema typically follows a progression through three distinct stages. The initial exudative stage involves the accumulation of sterile pleural fluid. This progresses to the fibropurulent stage, where bacteria invade the fluid and fibrin deposition begins. Finally, the organizing stage sees the formation of thick pleural peels that can trap the lung and prevent proper expansion. Understanding these stages is crucial for determining appropriate treatment strategies.

While empyema can affect individuals of any age, certain populations face higher risks. Children under five years and adults over 65 years show increased susceptibility. The condition carries significant morbidity, with hospital stays averaging 2-4 weeks and mortality rates ranging from 2-30% depending on patient factors and timely intervention. Early recognition and aggressive treatment remain paramount in improving outcomes and preventing long-term complications such as pleural thickening and restrictive lung disease.

Symptoms

The symptoms of empyema can vary depending on the stage of the disease, the causative organism, and the patient's overall health status. Early symptoms may be subtle and easily mistaken for persistent pneumonia, while advanced cases present with more severe manifestations.

Primary Respiratory Symptoms

• Sharp chest pain - Pleuritic pain that worsens with breathing, coughing, or movement
• Cough - Often dry initially, may become productive with foul-smelling sputum
• Shortness of breath - Progressive dyspnea due to lung compression and impaired expansion
• Rapid, shallow breathing - Compensatory mechanism to minimize chest pain
• Decreased breath sounds - On the affected side during physical examination
• Dullness to percussion - Over the area of fluid collection

Systemic Symptoms

• High fever - Often above 102°F (38.9°C), may be hectic or spiking
• Chills and rigors - Particularly with bacterial sepsis
• Night sweats - Profuse sweating, especially during sleep
• Fatigue and weakness - Profound exhaustion disproportionate to activity
• Loss of appetite - Leading to unintentional weight loss
• General malaise - Feeling unwell without specific symptoms

Associated Symptoms

• Leg pain - May occur due to referred pain or systemic inflammation
• Shoulder pain - Referred pain from diaphragmatic irritation
• Abdominal discomfort - With lower pleural space involvement
• Confusion or altered mental status - In elderly patients or with sepsis
• Clubbing of fingers - In chronic cases
• Cyanosis - Blue discoloration of lips and fingernails in severe cases

Pediatric Symptoms

Children with empyema may present differently than adults:

• Irritability and restlessness
• Poor feeding or refusal to eat
• Grunting respirations
• Nasal flaring
• Use of accessory muscles for breathing
• Lethargy or decreased activity

Causes

Empyema develops when bacteria or other microorganisms infect the pleural space. This can occur through various mechanisms, with bacterial pneumonia being the most common precipitating factor.

Primary Causes

• Pneumonia (40-60% of cases):
  • Community-acquired pneumonia
  • Hospital-acquired pneumonia
  • Aspiration pneumonia
  • Necrotizing pneumonia
• Post-surgical complications:
  • Thoracic surgery (lobectomy, pneumonectomy)
  • Esophageal surgery
  • Cardiac surgery
  • Post-operative infections
• Chest trauma:
  • Penetrating chest injuries
  • Blunt trauma with hemothorax
  • Retained hemothorax

Common Causative Organisms

• Aerobic bacteria:
  • Streptococcus pneumoniae (most common in community-acquired)
  • Staphylococcus aureus (including MRSA)
  • Streptococcus pyogenes
  • Klebsiella pneumoniae
  • Pseudomonas aeruginosa
  • Haemophilus influenzae
• Anaerobic bacteria:
  • Bacteroides species
  • Peptostreptococcus
  • Fusobacterium
  • Prevotella
• Other organisms:
  • Mycobacterium tuberculosis
  • Fungi (in immunocompromised patients)
  • Parasites (rare)

Pathophysiology

• Direct extension: Bacteria spread from adjacent pneumonia
• Hematogenous spread: Through bloodstream from distant infection
• Lymphatic spread: Via lymphatic channels
• Iatrogenic introduction: During procedures or surgery
• Transdiaphragmatic: From abdominal infections
• Esophageal rupture: Boerhaave syndrome or perforations

Risk Factors

Several factors increase the likelihood of developing empyema:

• Age extremes: Very young children and elderly adults
• Immunosuppression:
  • HIV/AIDS
  • Chemotherapy
  • Organ transplantation
  • Chronic corticosteroid use
• Chronic lung diseases:
  • COPD
  • Bronchiectasis
  • Cystic fibrosis
  • Lung cancer
• Comorbid conditions:
  • Diabetes mellitus
  • Alcoholism
  • Intravenous drug use
  • Malnutrition
  • Liver cirrhosis
  • Chronic kidney disease
• Recent medical events:
  • Recent pneumonia
  • Thoracic procedures
  • Chest tube placement
  • Central line insertion
• Social factors:
  • Homelessness
  • Overcrowded living conditions
  • Poor dental hygiene
  • Aspiration risk

Diagnosis

Diagnosing empyema requires a combination of clinical assessment, imaging studies, and pleural fluid analysis. Early and accurate diagnosis is essential for appropriate management and improved outcomes.

Clinical Evaluation

• History taking: Duration of symptoms, recent pneumonia, risk factors
• Physical examination:
  • Decreased breath sounds
  • Dullness to percussion
  • Decreased tactile fremitus
  • Pleural friction rub (early stages)
  • Mediastinal shift (large effusions)

Imaging Studies

• Chest X-ray:
  • Pleural effusion with meniscus sign
  • Loculated fluid collections
  • Air-fluid levels (bronchopleural fistula)
  • Pleural thickening
• Chest CT scan:
  • Split pleura sign (enhanced visceral and parietal pleura)
  • Loculations and septations
  • Pleural thickening
  • Underlying lung pathology
  • Mediastinal lymphadenopathy
• Ultrasound:
  • Echogenic fluid
  • Septations and loculations
  • Pleural thickening
  • Guide for thoracentesis

Pleural Fluid Analysis

• Gross appearance: Thick, purulent, foul-smelling
• Cell count: WBC >50,000/μL, predominantly neutrophils
• pH: <7.2 (indicates need for drainage)
• Glucose: <40 mg/dL
• LDH: >1000 IU/L
• Protein: >3 g/dL
• Gram stain and culture: Identify causative organism
• AFB stain: If tuberculosis suspected

Additional Tests

• Blood tests:
  • Complete blood count (leukocytosis)
  • C-reactive protein and ESR (elevated)
  • Blood cultures
  • Liver and kidney function
• Bronchoscopy: If endobronchial obstruction suspected
• Video-assisted thoracoscopy (VATS): For diagnosis and treatment

Treatment Options

Treatment of empyema requires a multimodal approach combining antibiotic therapy, drainage of infected fluid, and supportive care. The choice of treatment depends on the stage of empyema, patient factors, and response to initial therapy.

Antibiotic Therapy

• Empirical therapy:
  • Beta-lactam/beta-lactamase inhibitor combinations
  • Third-generation cephalosporin + metronidazole
  • Carbapenem for severe cases
  • Add vancomycin if MRSA suspected
• Targeted therapy: Based on culture results
• Duration: Typically 2-6 weeks depending on response
• Route: Initial IV therapy, transition to oral when stable

Drainage Procedures

• Thoracentesis:
  • Diagnostic and therapeutic
  • May require repeated procedures
  • Limited efficacy in loculated effusions
• Chest tube drainage:
  • Standard treatment for most cases
  • Large-bore (24-32 Fr) or small-bore (10-14 Fr) tubes
  • Continuous drainage with water seal
  • May require multiple tubes for loculated collections
• Intrapleural fibrinolytic therapy:
  • tPA (tissue plasminogen activator) + DNase
  • Helps break down loculations
  • Improves drainage in complex cases
  • Reduces need for surgery in some patients

Surgical Interventions

• Video-assisted thoracoscopic surgery (VATS):
  • Minimally invasive approach
  • Debridement and decortication
  • Breaking down adhesions
  • Earlier recovery than open surgery
• Open thoracotomy with decortication:
  • For advanced organizing stage
  • Removal of fibrous peel
  • Re-expansion of trapped lung
  • Higher morbidity but definitive treatment
• Thoracoplasty or window thoracostomy:
  • For patients unable to tolerate major surgery
  • Chronic empyema management
  • Open drainage procedures

Supportive Care

• Pain management: Adequate analgesia for chest pain
• Respiratory support:
  • Oxygen therapy
  • Incentive spirometry
  • Chest physiotherapy
  • Early mobilization
• Nutritional support: High-protein diet, supplements if needed
• Thromboprophylaxis: Prevention of blood clots
• Treatment of complications: Sepsis, respiratory failure

Treatment Algorithm

• Stage 1 (Exudative): Antibiotics ± thoracentesis
• Stage 2 (Fibropurulent): Antibiotics + chest tube ± fibrinolytics
• Stage 3 (Organizing): Antibiotics + surgical intervention
• Failed medical management: Consider surgery after 5-7 days

Prevention

Preventing empyema focuses on reducing risk factors and promptly treating conditions that can lead to its development:

• Pneumonia prevention:
  • Pneumococcal vaccination (PCV13, PPSV23)
  • Annual influenza vaccination
  • COVID-19 vaccination
  • Haemophilus influenzae type b vaccine
• Early treatment:
  • Prompt antibiotic therapy for pneumonia
  • Appropriate follow-up care
  • Recognition of treatment failure
  • Early drainage of parapneumonic effusions
• Risk factor modification:
  • Smoking cessation
  • Good oral hygiene
  • Management of chronic diseases
  • Alcohol moderation
  • Nutritional optimization
• Post-surgical care:
  • Sterile surgical technique
  • Prophylactic antibiotics when indicated
  • Early mobilization
  • Respiratory exercises
  • Proper chest tube management
• Aspiration prevention:
  • Elevate head of bed for at-risk patients
  • Swallowing assessment
  • Modified diet textures
  • Treatment of GERD

When to See a Doctor

Seek medical attention if you experience:

• Persistent sharp chest pain that worsens with breathing
• High fever (above 101°F/38.3°C) lasting more than 2-3 days
• Shortness of breath or difficulty breathing
• Productive cough with foul-smelling sputum
• Chest pain following recent pneumonia
• Failure to improve after pneumonia treatment
• Night sweats and unintentional weight loss
• Recent chest surgery or trauma with new symptoms

Seek emergency care immediately for:

• Severe difficulty breathing or gasping for air
• Confusion or altered mental status
• Blue discoloration of lips or fingernails
• Severe chest pain with lightheadedness
• Signs of septic shock (low blood pressure, rapid heart rate)
• Coughing up large amounts of blood

Related Conditions

Frequently Asked Questions

References

1. Shen KR, et al. The American Association for Thoracic Surgery consensus guidelines for the management of empyema. J Thorac Cardiovasc Surg. 2017;153(6):e129-e146.
2. Rahman NM, et al. Intrapleural use of tissue plasminogen activator and DNase in pleural infection. N Engl J Med. 2011;365(6):518-526.
3. Brims FJ, et al. Empyema thoracis: new insights into an old disease. Eur Respir Rev. 2010;19(117):220-228.
4. Davies HE, Davies RJ, Davies CW; BTS Pleural Disease Guideline Group. Management of pleural infection in adults: British Thoracic Society Pleural Disease Guideline 2010. Thorax. 2010;65 Suppl 2:ii41-53.
5. Redden MD, et al. Surgical versus non-surgical management for pleural empyema. Cochrane Database Syst Rev. 2017;3(3):CD010651.