Fibrothorax

Fibrothorax is extensive fibrous thickening of the visceral and parietal pleura, encasing and restricting the lung, with loss of thoracic volume.

• Causes: organised haemothorax (trauma, surgery), empyema, tuberculous pleurisy, asbestos exposure (diffuse pleural thickening), uraemic pleuritis, rheumatoid disease, drug induced (dopamine agonists: ergot derivatives, methysergide, amiodarone), radiation, connective tissue disease, previous pleurodesis, post cardiac surgery.
• Pathology: persistent fibrin deposition, failure of fibrinolysis, collagen deposition by mesothelial cell transformation.
• Differs from trapped lung (visceral pleural peel preventing re-expansion with pleural effusion present), fibrothorax is a chronic, fixed thickening, possibly calcified.
• Complications: restrictive ventilatory defect, chronic dyspnoea, respiratory failure, recurrent infection, chest wall contraction and scoliosis, pulmonary hypertension.

• Progressive exertional dyspnoea, chest tightness or dull pain, reduced chest wall movement on the affected side, flattened chest, crowded ribs.
• Dullness to percussion, diminished breath sounds, clubbing absent.
• History of empyema, haemothorax, tuberculosis, asbestos.

• Chest radiograph: pleural thickening, calcification, volume loss, mediastinal shift toward the affected side, crowding of ribs.
• CT chest with contrast: smooth uniform pleural thickening over 3 mm, extending over more than 5 cm craniocaudally and 8 cm laterally, calcification, loculated residual fluid, rind; distinguish from malignant pleural disease (nodular, mediastinal pleural involvement, over 1 cm thickness, circumferential).
• Pulmonary function tests: restriction, reduced vital capacity; ventilation perfusion scan shows reduced ventilation and perfusion of the affected lung.
• PET CT or biopsy (image guided, thoracoscopic) if malignancy suspected (mesothelioma in asbestos exposed).
• Pleural fluid analysis if effusion present; TB testing.

• Treat underlying cause; stop causative drugs (ergot dopamine agonists).
• Early prevention: adequate drainage of haemothorax and empyema, intrapleural fibrinolytic therapy (alteplase 10 mg with DNase 5 mg twice daily for 3 days) and early VATS.
• Decortication (open thoracotomy or VATS pleurectomy) for symptomatic patients with restrictive physiology, a viable underlying lung (confirmed by V/Q scan or CT), and failed medical therapy; improves lung function by 20 to 30% in selected patients, best within 3 to 6 months of onset; high morbidity (air leaks, bleeding, mortality 2 to 10%).
• Corticosteroids (prednisolone 30 to 40 mg daily) in benign asbestos pleural disease, uraemic pleuritis and rheumatoid pleurisy (limited benefit).
• Intensive dialysis for uraemic fibrothorax.
• Supportive: pulmonary rehabilitation, oxygen, bronchodilators, vaccinations, respiratory muscle training, chest physiotherapy.
• Conservative management for asymptomatic or mild disease; follow with serial imaging and lung function.
• Occupational compensation for asbestos related disease; surveillance for mesothelioma.