interstitial & occupational lung disease Flashcards
what is an interstitial disease?
any disease which affects the lung interstitium (i.e alveoli & terminal bronchi).
it interferes with gas transfer and produces a restrictive pattern on spirometry
what are the two main symptoms of interstitial disease?
(progressive) breathlessness and dry cough
how can interstitial disease be classified?
acute, episodic or chronic
how does chronic interstitial disease arise?
as part of systemic disease, due to exposure to a damaging agent and idiopathically
whats is sarcoidosis?
a multi-system granulamatous (type IV) hypersensitivity disease to an unknown antigen
what are the common organs involved in sarcoidosis?
lungs, lymph nodes, liver, skin, joints and eyes
sarcoidosis is less common in smokers. true/false
true
what are the characteristics of acute sarcoidosis?
erythema nodosum, bilateral hilar lymphadenopathy, arthritis, uveiti, parotidis, fever
what are the characteristics of chronic sarcoidosis?
lung infiltrates (alveolitis), skin infiltrates, peripheral lymphadenopathy, hypercalcaemia, splenomegaly
what investigations would we do for suspected sarcoidosis? what would we expect to see?
CXR (BHL), CT scan (peripheral nodular infiltrate), biopsy (non-caseating granulomas) , spirometry (restrictive defect), bloods (raised ACE, raised calcium, inc. inflam markers)
how would we treat acute and chronic sarcoidosis?
acute - usually self limiting
chronic - oral steroids (if vital organ affected) and immunosuppression (azathioprine, methotrexate & anti-TNF)
do we monitor people who have/have had sarcoidosis?
YES
what is extrinsic allergic alveolitis (EAA)?
a type III hypersensitivity reaction to an allergen causing lymphocytic alveolitis (hypersensitivity pneumonitis)
what causes EAA?
allergens such thermophilic actionmycetes, avian antigens and certain drugs
what is the acute presentation of EAA?
symptoms occur hours after exposure, cough, breathlessness, fever, myalgia, crackles with NO wheeze, hypoxia, widespread pulmonary infiltrates on CXR
how do we treat acute EAA?
oxygen, steroids & avoidance
what is the presentation of chronic EAA?
progressive breathlessness, cough, crackles, upper zone fibrosis on CXR, restrictive spirometry, reduced TLCO, precipitins on serology
(NO CLUBBING!)
how do we treat chronic EAA?
oral steroids (+breathless/low TLCO) and avoidance/removal of antigen
what is idiopathic pulmonary fibrosis (IPF)?
fibrosis of the lung interstitium due to an imbalance in fibrotic repair system of unknown causes
what is the most common interstitial lung disease?
IPF
is IPF an inflammatory disease?
NO
IPF is less common in smokers. T/F
False
what are some causes of pulmonary fibrosis?
rheumatoid arthritis, SLE, sclerosis, asbestos, drugs (amiodarone, methotrexate, etc)
how does IPF present?
progressive breathlessness, dry cough, clubbing, bilateral fine inspiratory crackles, restrictive spirometry, reduced TLCO, bilateral infiltrates on CXR, reticulonodular (honeycombing) fibrotic change worst at lung bases
what does ground-glass on a CT scan suggest?
reversible alveolitis
what is the pathology of IPF?
chronic inflammatory infiltrate with neutrophils and fibrosis in alveolar walls with/without intra-alveolar macrophages
how to we treat IPF?
nothing really works. oxygen if hypoxic, lung transplant in young patients.
what is pneumoconiosis?
a disease of the lungs due to the inhalation of dust characterised by inflammation, coughing and fibrosis
what is simple pneumoconiosis?
chest x-ray abnormalities only
what is complicated pneumoconiosis?
impairment of lung function associated breathlessness and restrictive spirometry due to progressive mass fibrosis
what is Caplan’s syndrome?
rheumatoid pneumoconiosis
what is silicosis?
simple (egg shell calcification of hilum) or restrictive defect due to prolonged exposure to quartz (mining, foundry worker, etc)
what can exposure to high dose asbestos cause?
plerual plaques, acute pleuritis, pleural effusion/thickening, mesothelioma, diffuse pulmonary fibrosis (asbestosis) & bronchial carcinoma
in asbestosis we find asbestos fibres in the sputum and asbestos bodies in the lung. T/F
False - asbestos bodies in the sputum and asbestos fibres in the lung
how does pleuritis present?
pain, fever, blood pleural effusion
how does mesothelioma present?
chest pain & pleural effusion
