Asbestos and the lung

Question 1

Mechanisms of asbestos exposure (6)

Answer 1

• occupational exposure
  
  • Mining, milling, and transport of asbestos
  • Use of asbestos products, e.g. in construction and demolition
• domestic exposure
  
  • Relatives of asbestos workers exposed to ‘carry home’ asbestos in hair or clothes
  • Following remodelling or renovation in contaminated buildings
  • Local geological exposure from natural deposits, e.g. areas of central and south-east Turkey, north-west Greece, and Corsica
  • Urban environment (although undisturbed and non-friable asbestos building insulation is not considered hazardous).

Question 2

Types of asbestos related lung disease (7)

Answer 2

• Benign asbestos-related pleural disease
  
  • Pleural plaques
  • Benign asbestos-related pleural effusion
  • Diffuse pleural thickening
  • Rounded atelectasis
• Asbestosis
• Mesothelioma
• Lung cancer (multiplicative risk from smoking).

Question 3

Asbestos latency period

Answer 3

20-40 years

Question 4

What is asbestosis

Answer 4

chronic interstitial fibrosis resulting from asbestos inhalation

Question 5

what factors affect asbestosis disease development (3)

Answer 5

1. degree and length of exposure
2. fibre type - amphibole fibres and more fibrogenic than chrysotile
3. cigarette smoking

Question 6

features of asbestosis (5)

Answer 6

1. insidious onset of breathlessness
2. dry cough
3. bibasal late-inspiratory crackles
4. finger clubbing
5. respiratory failure and cor pulmonale

Question 7

asbestosis investigations (3)

Answer 7

1. CXR
2. High-resolution CT - ground glass opacities
3. restrictive pattern on pulmonary function tests

Question 8

asbestosis mx (4)

Answer 8

1. supportive
2. influenza and pneumococcal vaccination
3. smoking cessation
4. occupational compensation

Question 9

mesothelioma features (5)

Answer 9

1. dull, diffuse chest pain
2. pleural effusion or thickening
3. breathlessness
4. fatigue and weight loss
5. paraneoplastic syndromes like DIC

Question 10

mesothelioma ix (5)

Answer 10

1. pleural fluid - straw coloured or bloody effusion
2. cytological analysis
3. pleural fluid glucose and pH
4. CXR and CT
5. biopsy

Question 11

poor prognostic features (9)

Answer 11

1. transdiaphragmatic muscle invasion
2. mediastinal lymph node involvement
3. female gender
4. age >75
5. chest pain
6. poor performance status
7. high WCC
8. thrombocytosis
9. non-epithelioid histology