Interstitial and Granulomatous Lung Disease Flashcards
What is sarcoidosis?
A multisystem inflammatory disease of unknown aetiology which is characterised by non-necrotising granulomatous inflammation and predominantly affects the lungs and intrathoracic lymph nodes
Sarcoidosis is a diagnosis of exclusion. T/F?
True
What systemic symptoms occur in sarcoidosis?
Fever Anorexia Fatigue Night sweats Weight loss
What lung symptoms occur in sarcoidosis?
Dyspnoea on exertion Cough Chest pain Wheezing Haemoptysis
Other than lung findings and systemic findings what other systems can be affected by sarcoidosis?
Pulmonary findings Dermatological manifestations Ocular manifestations Cardiac manifestations Neurologic manifestations
What are the four radiographic stages of sarcoidosis?
1 - Bilateral hilar lymphadenopathy without infiltration
2 - Bilateral hilare lymphadenopathy with infiltration
3 - Infiltration alone
4 - Fibrotic bands, bullae, hilarious retraction, bronchiectasis and diaphragmatic tenting
The radiographic stages of sarcoidosis indicate disease chronicity or correlate with changes in pulmonary function. T/F?
False
What age of patients are affected with idiopathic pulmonary fibrosis?
> 50 years old
What are the signs of idiopathic pulmonary fibrosis?
Breathlessness Bibasilar crackles Clubbing Honeycombing Peripheral interstitial pattern
What are the symptoms of idiopathic pulmonary fibrosis?
Breathlessness which is worse with exercise Hacking dry cough Fatigue Weakness Appetite Weight loss Clubbing
What are the possible causes of pulmonary fibrosis?
Occupational and environmental - silicosis, asbestosis, hypersensitivity pneumonitis
Drug induced - amiodarone, nitrofurantoin, methotrexate, cocaine
Connective tissue disease - lupus, RA, scleroderma
Primary diseases - sarcoidosis, LAM
Idiopathic
Genetic
How is pulmonary fibrosis diagnosed?
High resolution CT
Extrinsic allergic alveolitis is mediated by which cells?
T cell mediated response
What are the symptoms of extrinsic allergic alveolitis?
Flu-like illness Cough High fever/chills Dyspnoea Chest tightness Malaise Myalgia
In chronic extrinsic allergic alveolitis what signs/symtpoms occur?
Dyspnoea in strain Sputum culture Fatigue Anorexia Weight loss
What is the presentation of extrinsic allergic alveolitis?
Small <5mm opacities throughout both lungs, sometimes sparing the apices and bases
There is airspace disease which is usually seen as ground glass opacities and fine reticulation
What are the characteristic of idiopathic pulmonary fibrosis on CXR?
Bibasal reticular abnormalities with a ground glass appearance
What are the charaterstics of idiopathic pulmonary fibrosis on high resolution CT?
Subpleural reticular abnormalities
Honeycombing
Traction bronchiectasis
‘Honeycombing’ can be seen on imaging of the lung in idiopathic pulmonary fibrosis. What does this mean?
Thick walled cysts 0.5 - 2cm in diameter in respiratory and terminal bronchioles
What is the appearance of idiopathic pulmonary fibrosis on histology?
Dense interstitial fibrosis predominantly in the sub-pleural region
Destruction of normal lung architecture
Cystically dilated air spaces and intervening fibrous tissue
Inflammatory infiltrate of lymphocytes, plasma cells and intra-alveolar macrophages
Few fibroblastic foci
Describe the pathogenesis of idioapthic pulmonary fibrosis.
Repeated cycles of epithelial activation and injury by an unknown agent. Abnormal activation of epithelial cells leads to a dysrgeulated repair process which causes the formation of fibroblastic foci and promotes fibrosis.
What cytoline released from damaged epithelial cells in idiopathic pulmonary fibrosis leads to the increased development of myofibroblasts?
TGF beta one
What can be used to treat idiopathic pulmonary fibrosis?
Pirfenidone Nintedanib Long term oxygen therapy Diuretics N-acetyl cysteine Antibiotics Lung transplantation
How does pirfenidone act to slow lung function decline in idiopathic pulmonary fibrosis?
It is an antifibrotic and has anti-inflammatory effects. It is thought to suppress fibroblast proliferation.
