Flashcards in Interstitial Lung Disease Deck (53):
What does interstitial disease cause?
Impaired gas transfer and a restrictive lung pattern.
What are the symptoms of interstitial lung disease?
Breathlessness and a dry cough.
What types of interstitial lung disease do we get?
Acute, episodic or chronic.
What are some general causes of interstitial lung disease?
Can be part of a systemic disease,
Environmental - exposure to an agent e.g. A drug or radiation.
Hypersensitivity - mouldy hay or avian proteins.
idiopathic e.g. Connective tissue disease or fibrosing alveolitis.
What are the two stages of change in interstitial lung disease and what do they involve?
Early - alveolitis - injury with inflammatory cell infiltration.
Late - characterised by fibrosis.
What causes the clinical effects of interstitial lung disease?
Effects due to hypoxia (respiratory failure) and cardiac failure.
What test should we do to diagnose the cause of interstitial lung disease?
Trans bronchial biopsy and thorascopic biopsy.
What biopsy is better and why?
Thorascopic as it is more reliable and generates more tissue.
What are the different types of chronic interstitial lung disease?
extrinsic allergic alveolitis (hypersensitivity pneumonitis), pneumoconiosis
and connective tissue disease.
What are other names for fibrosing alveolitis and what is it?
Cryptogenic fibrosing alveolitis or usual interstitial pneumonia.
It is a progressive interstitial fibrosis of an unknown cause.
What finding in the hands is common in fibrosing alveolitis?
What is the pathology of fibrosing alveolitis?
Subpleural and basal fibrosis.
Inflammatory component variable.
Terminal lung structure replaced by dilated spaces surrounded by fibrous walls.
What is extrinsic allergic alvaolitis otherwise called and what is it?
It is an acute or chronic inflammatory disease of the small airways and interstitium with occasional granulomas.
It is allergic in origin, type III or IV reaction.
What are the causes of EAA?
Thermopilic bacteria e.g. Farmers lung.
Avian proteins e.g. Bird fanciers lung.
Fungi - malt workers lung.
What can we detect from blood tests for EAA? What happens in unusual cases?
Precipitins e.g. Antibodies are often detectable in serum. Unusual cases come to biopsy.
What is sarcoidosis? What causes it?
Multi system granulomatous disorder (type 4 hypersensitivity reaction) of unknown cause. Pulmonary involvement is common. Most cases are mild and self limiting.
What are the common areas that sarcoidosis affects?
Lungs, lymph nodes, joints, liver, skin and eyes.
What are less common areas involved in sarcoidosis?
Kidneys, brain, nerves and heart.
What population of patients is sarcoidosis less common in?
What are 4 other manifestations of sarcoidosis?
Uveitis, erythema nodosum, lymphadenopathy and hypercalcaemia.
What are manifestations of acute sarcoidosis? And what is the treatment?
Erythema nodosum, bilateral hilar lymphadenopathy, arthritis, uveitis, parotitis and fever.
It is self limiting.
What are manifestations of chronic sarcoidosis? And what is the treatment?
Lung infiltrates (alveolitis), skin infiltrations, peripheral lymphadenopathy and hypercalcaemia.
Oral steroids are given if a vital organ is affected e.g. Lung, eyes, heart and brain.
Monitor CXR and pulmonary function test for years.
What are the tests for sarcoidosis? What are they looking for?
CXR - BHL.
CT of lungs - peripheral nodular infiltrate.
Pulmonary function - restrictive pattern due to infiltrates.
Blood tests - ACE levels as a marker of activity (not diagnostic), raised calcium and increased inflammatory markers.
What types of pulmonary involvement do we get in connective tissue disease?
Interstitial fibrosis (less severe than fibrosing alveolitis). Pleural effusions and rheumatoid nodules.
What is pneumoconiosis?
Lung disease caused by mineral dust exposure e.g. Asbestosis or silicosis.
What factors does pneumoconiosis depend upon?
Particle size, particle reactivity, clearance of particle and host response.
What is asbestos and its different shapes?
Straight - amphibole.
What can asbestos exposure cause?
Parietal pleural plaques, interstitial fibrosis (asbestosis), bronchial carcinoma and mesothelioma.
What are the symptoms of acute EAA?
When do symptoms occur?
Cough, breathlessness, fever, myalgia.
Classically symptoms occur several hours after acute exposure.
What are the symptoms of chronic EAA?
Progressive breathlessness and cough.
What are the signs of acute EAA?
Maybe pyrexia, crackles but no wheeze and hypoxia.
What is the treatment of acute EAA?
Oxygen, steroid and antigen avoidance.
What are the investigations of chronic EAA?
History of exposure, precipitins (IgG antibodies to antigen).
Lung biopsy if in doubt.
What is the treatment of chronic EAA?
Remove antigen exposure and give oral steroids of breathless or has low gas exchange.
What causes chronic EAA?
Repeated low dose antigen exposure over years.
What are the signs of chronic EAA?
May be crackles, clubbing is rare.
What will we see on pulmonary function tests for chronic EAA?
Restrictive defect - low FeV1 and FVC. High or normal ration.
Low gas transfer.
What is the most common interstitial lung disease?
Idiopathic pulmonary fibrosis.
What are secondary causes of pulmonary fibrosis?
Rheumatoid, SLE, systemic sclerosis and asbestosis.
What is the clinical presentation of pulmonary fibrosis?
Progressive breathlessness and a dry cough.
What do we see on examination for pulmonary fibrosis?
Clubbing, bilateral fine inspiratory crackles.
What investigations do we do for pulmonary fibrosis? What will we find?
Pulmonary function tests - reduced FEV1 and FVC with normal or raised FEV1/FVC ratio. Reduced lung volumes and low gas transfer.
CXR - bilateral infiltrates.
CT scan - fibrotic change worse at lung bases. Ground glass appearance suggests reversible alveolitis.
Lung biopsy - not necessary if CT scan is diagnostic.
What is the pathology of pulmonary fibrosis?
Chronic inflammatory infiltrate.
Neutrophils and fibrosis in alveolar walls +/- intra alveolar macrophages.
What is the prognosis for pulmonary fibrosis?
Most patients progress into respiratory failure and are dead in 5 years.
What do we see on investigation for Simple pneumoconiosis?
Chest X-ray abnormality but no impairment if lung function.
What is silicosis? What causes it? What signs does it have?
15-20 years exposure to Quartz - mining, foundry, glass, boilers.
Shows egg shell calcification of hilar nodes on chest X-ray only.
What are the symptoms of chronic silicosis?
Restrictive pattern with pulmonary fibrosis.
Where were people exposed to asbestos?
Mining, construction, shipbuilding, boilers and piping and with cars e.g. Brakes.
What is the pathogenesis of asbestos contact to mesothelioma?
Contact ==> Asymptomatic benign pleural plaques ==> acute asbestos pleuritis ==> pleural effusion and diffuse pleural thickening ==> malignant mesothelioma.
What signs and symptoms do you get with acute asbestos pleuritis?
Fever, pain, bloody pleural effusion.
What is malignant mesothelioma?
Incurable pleural cancer. Presents with chest pain and pleural effusion. No available treatment. Fatal within two years.
Where will we find asbestos bodies?
In sputum and lung biopsy.