What is pleurisy, its causes, and treatment options?

Pleurisy: Definition, Causes, and Treatment

Pleurisy is inflammation of the pleura (the membrane surrounding the lungs) characterized by sharp, stabbing chest pain that worsens with breathing, and is most commonly caused by viral infections, bacterial pneumonia, or pleural infection, requiring treatment with appropriate analgesics and antibiotics when bacterial infection is present. 1

Definition and Clinical Presentation

Pleurisy (also called pleuritis) presents with:

• Sharp, stabbing, or burning chest pain that worsens with breathing, coughing, or chest movement
• Pain that may radiate to the shoulder or back
• Shortness of breath due to limited chest expansion
• Possible pleural friction rub on auscultation
• May be associated with pleural effusion in some cases

Causes of Pleurisy

Infectious Causes

• Viral infections: Most common cause, including coxsackieviruses, respiratory syncytial virus, influenza, parainfluenza, mumps, adenovirus, cytomegalovirus, and Epstein-Barr virus 2
• Bacterial pneumonia: Leading to parapneumonic effusions or empyema
• Tuberculosis: Still a significant cause globally
• Other bacterial infections: Including atypical organisms

Non-infectious Causes

• Pulmonary embolism: Found in 5-21% of patients presenting with pleuritic chest pain 2
• Autoimmune disorders: Systemic lupus erythematosus, rheumatoid arthritis
• Malignancy: Primary or metastatic pleural disease
• Trauma: Including chest surgery or rib fractures
• Drug-induced pleurisy: Medications like ergotamine derivatives and bromocriptine 3
• Asbestos exposure: Can cause diffuse pleural thickening 4

Diagnostic Approach

Initial Evaluation

• Chest radiography: Essential first-line test to confirm pleural effusion or other abnormalities
• Blood tests: Complete blood count, inflammatory markers, blood cultures when infection is suspected
• Electrocardiogram: To rule out cardiac causes

Pleural Fluid Analysis (if effusion present)

• Differentiate between transudate and exudate (protein and LDH levels) 5
• Cellular differential count
• Microbiology: Gram stain, bacterial and mycobacterial cultures
• pH measurement: pH <7.2 indicates need for drainage 1
• Glucose and LDH levels: Low glucose (<3.3 mmol/L) and high LDH (>900 IU/L) suggest infection 1

Advanced Imaging

• CT scan: For better characterization of pleural and lung abnormalities
• Ultrasound: Helpful for detecting small effusions and guiding thoracentesis

Treatment Approach

1. Treating the Underlying Cause

For Viral Pleurisy

• Supportive care
• Pain management with NSAIDs 2
• Rest and adequate hydration

For Bacterial Pleural Infection

• Antibiotics: Start immediately upon identification of pleural infection 4, 1
  • Community-acquired infection:
    • IV options: Cefuroxime 1.5g TDS + metronidazole 400mg TDS, benzyl penicillin 1.2g QDS + ciprofloxacin 400mg BD, or meropenem 1g TDS + metronidazole 4, 1
    • Oral options: Amoxicillin 1g TDS + clavulanic acid 125mg TDS, amoxicillin 1g TDS + metronidazole 400mg TDS, or clindamycin 300mg QDS 4, 1
  • Hospital-acquired infection:
    • Piperacillin-tazobactam 4.5g QDS IV, ceftazidime 2g TDS IV, or meropenem 1g TDS IV 4, 1
  • Important note: Avoid aminoglycosides as they have poor penetration into the pleural space 4

For Pulmonary Embolism

• Anticoagulation therapy
• Consider thrombolysis for massive embolism

2. Drainage of Pleural Effusion (if present)

Indications for drainage 1:

• Frank pus (empyema)
• pH <7.2
• Glucose <3.3 mmol/L
• LDH >900 IU/L
• Large effusions causing symptoms
• Loculated collections

Drainage technique 4, 1:

• Use small-bore chest tubes (14F or smaller) under ultrasound guidance
• Connect to underwater seal drainage system
• Ensure tube patency by flushing with saline if drainage is poor
• For loculated effusions, consider intrapleural fibrinolytic therapy with tissue plasminogen activator (TPA) and DNase

3. Pain Management

• NSAIDs are first-line for pain relief in viral or non-specific pleurisy 2
• Acetaminophen as an alternative
• Consider intercostal nerve blocks for severe pain
• Avoid respiratory depression with judicious use of opioids

4. Surgical Intervention

Consider surgical referral if 4, 1:

• Patient fails to improve after 5-7 days of drainage and antibiotics
• Persistent sepsis with residual pleural collection
• Organized empyema requiring decortication
• Multiloculated effusions not responding to tube drainage

Video-assisted thoracoscopic surgery (VATS) is preferred over thoracotomy due to reduced morbidity 1

Monitoring and Follow-up

• Track temperature, white blood cell count, clinical symptoms, and radiographic improvement 1
• Reassess antibiotic coverage if no improvement after 48-72 hours
• For patients with pneumonia, smokers, and those >50 years, obtain follow-up chest radiography 6 weeks after treatment 2
• Consider underlying malignancy in cases of recurrent or persistent pleurisy

Common Pitfalls to Avoid

• Delaying drainage of complicated parapneumonic effusions
• Using aminoglycosides as sole therapy due to poor pleural penetration
• Removing chest tubes prematurely
• Failing to adjust antibiotics based on culture results
• Misdiagnosing the underlying cause of pleurisy 1