14/12/2025
Pleural effusion is the accumulation of excess fluid in the pleural cavity, the space between the lungs and the chest wall.
Causes
Pleural effusion can result from many conditions, mainly divided into two types:
1. Transudative effusion (caused by systemic factors)
• Congestive heart failure (most common)
• Cirrhosis (liver failure)
• Nephrotic syndrome
• Hypoalbuminemia
2. Exudative effusion (caused by local inflammation or infection)
• Pneumonia (parapneumonic effusion)
• Tuberculosis (TB)
• Pulmonary embolism
• Cancer (lung, breast, lymphoma, etc.)
• Autoimmune diseases (like rheumatoid arthritis, lupus)
Symptoms
• Shortness of breath (dyspnea)
• Chest pain (especially on deep breathing)
• Dry cough
• Fever (if infection present)
Diagnosis
1. Chest X-ray – shows fluid level
2. Ultrasound or CT scan – confirms and measures the fluid
3. Pleural tapping (thoracentesis) – fluid analysis helps determine cause:
• Protein & LDH levels → Transudate vs Exudate (Light’s criteria)
• Cell count, cytology, culture, AFB → infection, malignancy, TB, etc.
Treatment
• Treat the underlying cause
• Pleural tapping (thoracentesis) – to relieve pressure and for diagnosis
• Chest tube drainage – for large or infected effusions (empyema)
• Pleurodesis – in recurrent malignant effusions