Interstitial Lung Disease Flashcards
What does ILD stand for?
Interstitial Lung Disease
ILD is an umbrella term for many conditions causing inflammation and fibrosis of the lung parenchyma and interstitium.
What is the lung parenchyma?
Functional tissue of the lungs, including alveoli, bronchioles, and blood vessels involved in gas exchange.
What is the lung interstitium?
Thin, supportive network of connective tissue within lung parenchyma, containing fibroblasts, collagen, and immune cells.
What happens to the lung interstitium in ILD?
It becomes inflamed or fibrotic, affecting gas exchange and lung function.
What role do fibroblasts play in ILD?
They respond to lung injury, but genetic mutations can lead to excess secretion of extracellular matrix, causing fibrosis.
What are examples of primary ILDs?
- Idiopathic pulmonary fibrosis
- Acute interstitial pneumonia
- Desquamative interstitial pneumonia
What are examples of secondary ILDs?
- Connective tissue and autoimmune diseases (e.g. sarcoidosis, rheumatoid arthritis)
- Infective causes (e.g. mycoplasma pneumonia)
- Environmental factors (e.g. asbestosis)
- Drugs (e.g. methotrexate)
What are common risk factors for ILD?
- Male sex
- Cigarette smoking
- Regular dust exposure (could be occupational)
What are typical symptoms of ILD?
- Progressive exertional dyspnoea
- Dry cough
- General malaise and fatigue
- +/- connective tissue disease symptoms
What are typical exam findings in ILD?
- Bilateral fine end-inspiratory crackles
- Finger clubbing
What are differential diagnoses for ILD?
- COPD
- Asthma
- Congestive cardiac failure
- Lung cancer
- Bronchiectasis
What does the diagnosis of ILD involve?
- Clinical features
- High-resolution CT scan of thorax
- Spirometry showing restrictive pattern
What does a high-resolution CT scan reveal in ILD?
Ground glass appearance.
What is the spirometry pattern in ILD?
Restrictive pattern with reduced FEV1 and reduced FVC.
Upper lung zone fibrosis can be associated with which conditions?
CHARTS
* Coal work pneumoconiosis
* Histiocytosis-X
* Ankylosing spondylitis
* Radiation
* Tuberculosis
* Sarcoidosis and silicosis
Lower lung zone fibrosis can be associated with which conditions?
RASIO
* Rheumatoid arthritis
* Asbestosis
* SLE, scleroderma, Sjogren’s syndrome
* Idiopathic pulmonary fibrosis
* Others (including drugs)
What are some conservative management strategies for ILD?
- Avoid underlying causes
- Smoking cessation
- Pulmonary rehabilitation
- Vaccinations (influenza and pneumococcal)
What is a medical management option for idiopathic pulmonary fibrosis?
- Pirfenidone
- Nintedanib
What is a medical management option for sarcoidosis?
Corticosteroids (prednisolone).
What is a medical management option for connective tissue disease-related ILD?
- Corticosteroids (prednisolone)
- Steroid-sparing agents (azathioprine or mycophenolate)
What causes extrinsic allergic alveolitis (hypersensitivity pneumonitis)?
- Bird-fanciers lung
- Farmers lung
- Mushroom workers lung
- Malt workers lung
What is the treatment for extrinsic allergic alveolitis?
Corticosteroids (prednisolone).
