Interstitial lung disease Flashcards
What is interstitial lung disease?
Lung disease in the interstitium, which is the layer between the alveolar epithelium and capillary endothelium. Characterised by chronic inflammation and/or progressive interstitial fibrosis.
Give 4 pathological findings in interstitial lung disease.
Usual interstitial pneumonia Non-specific interstitial pneumonia Dequamative interstitial pneumonia Diffuse alveolar damage [formative, from lecture 5.12.17]
Give 3 examples of interstital lung disease.
Idiopathic eg I. pulmonary fibrosis, non-specific interstitial pneumonitis
Known cause eg asbestosis, hypersensitivity pneumonitis
Systemic disorder-associated eg sarcoidosis, RA, ARDs/CTDs
Adult respiratory disress syndrome
What is idiopathic pulmonary fibrosis?
Interstitial scarring of unknown cause, causing difficulty breathing.
Give 3 risk factors for IPF.
Smoking GORD Infections eg herpes Asbestos exposure Family history of IPF.
Describe the pathology of IPF.
Type 2 pneumocytes can divide into type 1 or 2 pneumocytes. As part of the repair process, they overproliferate and cause thickening and stiffness of the interstitium. When fibroblasts are damaged they become myofibroblasts which thicken the interstitial layer.
Give 3 findings of lung function tests in ILDs.
Restrictive so:
Decreased total lung capacity, forced vital capacity and forced expiratory volume.
Give 3 symptoms of IPF.
Insidious progressive dyspnoea, persistent dry non-productive cough, tiredness, anorexia, weight loss, clubbed fingers.
Give 3 signs of IPF
Clubbing
Honeycomb cysts
Bi-basal end respiratory crackles
Pulmonary hypertension
Give 3 differential diagnoses of IPF.
Heart failure, COPD, sarcoidosis, pulmonary embolism, lung cancer, extrinsic allergic alveolitis.
Give 3 investigations you would do for IPF.
- Gold-standard: High-resolution CT - basal distribution, honeycombing, subpleural reticulation.
- Spirometry - restrictive -> decreased TLC, FEV and FVC, reduced TLCO.
- Blood tests - check ANA and RF, FBC, ESR, CRP
Chest X ray
Bronchioalveolar lavage
Lung biopsy -> tissue changes
Describe the management of IPF.
- Supportive - vaccinations against pneumonia, smoking cessation, oxygen if hypoxic
- Tyrosine kinase inhibitors eg nintedanib - antifibrotic, anti-inflammatory.
- Lung transplant is the only curative treatment
Give 3 complications of IPF.
Chest infections, pulmonary hypertension, heart failure. Bad prognosis, premature death.
What is sarcoidosis?
Multi-system granulomatous disease involving abnormal collections of inflammatory cells, affecting mainly lungs.
What is the pathology of sarcoidosis?
Destruction of normal tissue causes accumulations of epithelioid cells, macrophages and lymphocytes, forming a granuloma.
Diffuse parenchymal lung disease so can cause restrictive and obstructive disease.
Granulomas may present in skin as papules or rashes, in the eye as dry eyes or glaucoma. [holly]
