Asbestos-related Lung Disease Flashcards
What is asbestos?
a silicate of iron, magnesium, nickel, cadmium and aluminium that occurs naturally as fibres
What is the most common form of asbestos? (90%)
Chrysotile/ white asbestos (soft, long, thin fibre)
What is the second most common form of asbestos? (6%)
Crocidolite/ blue asbestos (long, thick fibre)
Which type of asbestos fibre is most likely to cause asbestosis and mesothelioma?
Crocidolite
Give two working environments where asbestos levels have been historically high:
1) shipping yards
2) power stations
What cancer does asbestos starkly increase the risk of?
primary lung adenocarcinoma
What are pleural plaques?
benign, scarred, calcified areas of thickened tissue that form in the pleura or lung lining secondary to asbestos exposure
What symptoms are associated with pleural plaques?
they are often asymptomatic but can cause mild restrictive ventilatory defects such as mild effort dyspnoea
What CXR signs would be associated with pleural plaques? (2)
1) parietal pleural thickening
2) calcification
Name 6 asbestos-related lung pathologies:
1) pleural plaques
2) pleural effusion
3) bilateral diffuse pleural thickening
4) mesothelioma
5) asbestosis
6) primary lung adenocarcinoma
How long after asbestos exposure can a pleural effusion occur?
within the first two decades
Give two presentations associated with pleural effusion:
1) pleuritic pain
2) dyspnoea
True or false: asbestos-associated pleural effusions are often recurrent
True
How does bilateral diffuse pleural thickening present on CXR?
thickening of both parietal and visceral pleural on both lungs(>5mm think and extending over more than 1/4 of the chest wall)
What is mesothelium?
simple squamous epithelium that lines the lungs and other serous cavities and internal organs
What is the main clinical presentation of bilateral diffuse pleural thickening?
Dysponoea
How long after initial asbestos exposure do mesotheliomas arise?
20-40 years
What 2 CXR findings are associated with mesotheliomas?
1) pleural thickening
2) pleural effusion (usually unilateral)
Give 6 signs and symptoms associated with mesothelioma:
1) pleuritic pain
2) progressive dyspnoea
3) haemoptysis
4) fatigue
5) anaemia
6) wheeze, hoarseness or cough
Give 4 sites where mesothelioma metastasis is common:
1) other lung
2) liver
3) adrenal gland
4) kidney
How is a mesothelioma diagnosed?
biopsy via thoracoscopy
What two chemotherapy drugs have shown promising results when combined?
1) cisplatin
2) pemetrexed
What is asbestosis?
fibrosis of the lung due to asbestos exposure
Is asbestosis associated with high or low exposure to asbestos?
high
How long after initial exposure to asbestos does asbestosis present?`
5-10 years
Give 4 symptoms associated with asbestosis:
1) progressive, worsening SOB
2) cough
3) wheeze
4) chest tightness
What hand sign is associated with asbestosis?
clubbing
True or false: there are many treatments available for asbestosis
false - there are no specific treatments and so has a poor prognosis
Describe the pathophysiology of asbestos-related lung diseases: (2)
1) asbestos fibres in pulmonary tissues activate a chronic inflammatory response, stimulating macrophages to activate fibroblasts - these deposit connective tissue
2) asbestos can bind to chromosomes and cause mutations
