Fibrotic lung disease

Fibrotic lung diseases are a group of disorders characterised by fibrosis and/or inflammation of the pulmonary interstitium.

1. Chronic inflammation leads to alveolar wall fibrosis and architectural distortion.
2. Results in reduced gas exchange and lung compliance.

• Idiopathic: e.g., Idiopathic Pulmonary Fibrosis (IPF).
• Occupational: e.g., Asbestosis, Silicosis.
• Drug-induced: e.g., Amiodarone, Methotrexate.
• Autoimmune: e.g., Rheumatoid arthritis, Systemic sclerosis, Sarcoidosis.
• Other: Radiation pneumonitis, hypersensitivity pneumonitis.

• Dyspnoea on exertion.
• Non-productive cough.
• Clubbing of fingers.
• Bilateral inspiratory ‘velcro’ crackles on auscultation.
• Features of specific aetiology (e.g. erythema nodosum in sarcoidosis).

• Chest X-ray: Reticulonodular shadowing, often basilar predominant.
• HRCT: Ground-glass opacities, honeycombing, and reticulation.
• Pulmonary function tests: Restrictive pattern with reduced diffusing capacity for carbon monoxide (DLCO).
• Bronchoalveolar lavage or lung biopsy in selected cases.

• General: Smoking cessation, vaccination (influenza, pneumococcal), and pulmonary rehabilitation.
• Idiopathic Pulmonary Fibrosis: Antifibrotic agents like pirfenidone and nintedanib.
• Autoimmune: Immunosuppression e.g., corticosteroids, cyclophosphamide.
• Oxygen therapy for those with hypoxemia.
• Lung transplantation: Considered in severe, progressive disease.

• Respiratory failure.
• Cor pulmonale.
• Increased risk of lung cancer.
• Exacerbations leading to rapid progression.

• Variable depending on the underlying cause.
• IPF has a poor prognosis with median survival of 2-5 years post-diagnosis.

• Fibrotic lung disease has multiple aetiologies which lead to chronic inflammation and fibrosis of the lung.
• Investigation is based on characteristic features found on imaging and pulmonary function testing.
• Bilateral inspiratory ‘velcro’ crackles on auscultation, honeycombing and ground-glass opacities on imaging as well as a restrictive lung function pattern are characteristic of fibrotic lung disease.
• Management varies but includes lifestyle changes, antifibrotic therapy (IPF) and immunosuppression (autoimmune).