ILD Flashcards
What are the main ILDs?
Idiopathic pulmonary fibrosis
Sarcoidosis
Extrinsic allergic alveoli’s (hypersensitivity pneumonitis)
What are ILDs?
Diseases affecting the interstitium
What pattern do ILDs have on spirometry?
Restrictive
What is the pathology of early stage ILD?
Alveolitis - injury and inflammatory cell infiltration that interferes with gas transfer
What is the pathology of late stage ILD?
Fibrosis, leading to hypoxia and cardiac failure
What is diagnosis based on?
Clinical failures and biopsy confirmation
What are the two methods for biopsy, and what are the pros and cons?
Transbronchial
Thorascopic - more invasive but more reliable
Which is the most common ILD?
Idiopathic pulmonary fibrosis
What is idiopathic pulmonary fibrosis?
Progressive interstitial fibrosis of unknown cause
What are the pathological changes in idiopathic pulmonary fibrosis?
Basal and sub-pleural fibrosis
Terminal lung structure replaced by dilated spaces surrounded by fibrosis
What are the symptoms of idiopathic pulmonary fibrosis?
Progressive breathlessness over years
Dry cough
What are the signs of idiopathic pulmonary fibrosis?
Finger clubbing
Bilateral fine inspiratory crackles
What investigations are done for idiopathic pulmonary fibrosis - and what is seen?
Spirometry - restrictive
Low gas transfer
CXR - bilateral infiltrates
CT - shadowing, worse at bases and periphery, traction bronchiectasis, honeycombing
When is a biopsy done for idiopathic pulmonary fibrosis?
Only if unsure after CT
What is the treatment for idiopathic pulmonary fibrosis?
Oxygen if hypoxic
Lung transplant
What is the prognosis and median survival after diagnosis for idiopathic pulmonary fibrosis?
Bad - 4 years
What is sarcoidosis?
Multi-system granulomatous disorder of unknown cause
What type of hypersensitivity is sarcoidosis?
Type 4
What is the presentation of acute sarcoidosis?
Erythema nodosum Bilateral hilar lymphadenopathy Arthritis Uveitis, parotitis Fever
What is the presentation of chronic sarcoidosis?
Lung infiltrates Skin infiltrates Peripheral lymphadenopathy Hypercalcaemia Other organ involvement
What investigations are done for sarcoidosis?
CXR CT Biopsy Spirometry Bloods (increased calcium)
What is seen on biopsy in sarcoidosis?
Non-caveating granulomas
What is the treatment for sarcoidosis?
Steroids
What is hypersensitivity pneumonitis?
Inflammatory condition of the small airways and interstitium with occasional granulomas caused by a trigger
What type of hypersensitivity is hypersensitivity pneumonitis?
Type 3 - immune complex mediated
What are the causes of hypersensitivity pneumonitis, and who are affected by each?
Thermophilic bacteria - farmers, malt workers, mushroom workers
Avian proteins - bird owners
Fungi
Drugs - sulphasalazine
What are the symptoms of acute hypersensitivity pneumonitis?
Cough
Breathlessness
Fever
Myalgia
When do symptoms of acute hypersensitivity pneumonitis come on?
Hours after exposure
What are the signs of acute hypersensitivity pneumonitis?
Fever
Crackles
Hypoxia
No wheeze
What is seen on CXR in acute hypersensitivity pneumonitis?
Widespread pulmonary infiltrates
What is the treatment for acute hypersensitivity pneumonitis?
Oxygen
Steroids
Antigen avoidance
What are the symptoms of chronic hypersensitivity pneumonitis?
Breathlessness
Cough
When do the symptoms of chronic hypersensitivity pneumonitis come on?
Over years
What are the signs of chronic hypersensitivity pneumonitis?
Crackles
What is seen on CXR in chronic hypersensitivity pneumonitis?
Pulmonary fibrosis, mostly upper zones
How is diagnosis made in chronic hypersensitivity pneumonitis?
History of exposure
Precipitins (IgG)
Lung biopsy if unsure
What is the treatment for chronic hypersensitivity pneumonitis?
Remove antigen exposure
Oral steroids if breathless or low gas transfer
