Occupational Lung Disease Flashcards
OCCUPATIONAL LUNG DISEASE
Exposure to noxious stimuli at work can cause Acute
Bronchitis and Pulmonary Oedema (e.g. SO2, Cl2, NH3, or
Oxides of Nitrogen), Pulmonary Fibrosis from Mineral dust,
Occupational Asthma (Commonest cause in developed
world), Hypersensitivity Pneumonitis, Bronchial Carcinoma
secondary to Industrial Agents
o Iron (Siderosis), Barium (Baritosis), Tin (Stannosis)
leads to dramatic dense nodular shadowing on CXR but effects are minimal, whereas
Silicosis or Asbestosis leads to extensive Fibrosis or Disability
Pneumoconiosis
Accumulation of dust in the lungs and tissue reaction; Refers to coal dust
Coal-Worker’s Pneumoconiosis
• Particles 2-5μm diameter; Retained in the Small Airways and Alveoli of lungs
• Improved ventilation and working conditions have reduced risk of disease
• Simple Pneumoconiosis – Deposition of Coal Dust in Lungs; Fine Micronodular shadowing on
CXR, graded by ILO Standards; Compensation for disability regardless of radiology
o Symptoms might be COPD-related to cigarette smoking (Confounding)
o Simple Pneumoconiosis can progress to Progressive Massive Fibrosis (PMF)
• Progressive Massive Fibrosis – Round Fibrotic masses; Upper Lobes and sometimes necrotic
central cavities; Associated with Fibrogenic promoting factors and Immune Complexes
o Caplan’s Syndrome – Large Fibrotic Nodules in coal miners with Rheumatoid Arthritis
o RF and ANA might be present in PMF, Asbestosis and Silicosis
o Apical destruction and disruption of lung resulting in Emphysema and Airway
Damage; Mixed Restrictive/Obstructive defect
o Loss of Lung Volume, Irreversible Airflow Limitation, Reduced Gas Transfer
• Considerable Effort Dyspnoea usually with productive cough (black sputum) – Can progress in
absence of coal dust to Respiratory Failure
Silicosis
- Uncommon – In Stone Masons, Sand-blasters etc; Caused by inhalation of SiO2
- Dust is highly Fibrogenic, toxic to Alveolar Macrophages
- Similar appearance to PMF but with Thin Hilar (Eggshell) calcification
Asbestos
• Asbestos is a mixture of metal silicates and occurs naturally as a fibre; Blue Asbestos
(Crocidolite) more Fibrogenic than White Asbestos (Chrysotile); Blue Asbestos more likely to
cause Silicosis and Mesothelioma
• Impaction of fibres in the lung; Resistant to Macrophage and Neutrophil Enzymatic
destruction; 20-40yr lag between exposure and disease (particularly Mesothelioma)
o Also increased risk of Primary Lung Cancer; Risk synergises with Smoking
• Reduced incidence with prohibition of Blue and strict restriction of White Asbestos use
• Clinical Presentations include Bilateral Diffuse Pleural Thickening, Asbestosis, Mesothelioma
and Asbestos-Related Carcinoma
Asbestosis
Lung ± Pleural Fibrosis; Progressive disease of SOB accompanied by Finger
Clubbing and Bibasal End-Inspiratory Crackles; Fibrosis seen better on High-res CT
o No treatment for disease modification; Corticosteroids prescribed
Mesothelioma
Most commonly presents as Pleural
Effusion with persistent Chest Wall pain even if
pleural fluid or biopsy non-diagnostic; Video Assisted
Thoracoscopic (VATS) Lung Biopsy for tissue biopsy
o Chemotherapy ± Surgery; Poor prognosis
Asbestos Exposure and Compensation in the United Kingdom
• At High-Risk occupations – Boiler, Construction,
Firefighters, Industrial, Factory, Shipyard, Textile Mill,
Power Plant workers
• Advice via Mesothelioma UK regarding making claims – Civil claim versus previous employers
o Industrial Injury Benefits if present “Prescribed Diseases” – Asbestosis,
Mesothelioma, Lung Cancer with Asbestosis (or without, if extensive occupational
exposure in specified occupations), Diffuse Pleural Thickening
• Diffuse Mesothelioma Payments (2008) or Diffuse Mesothelioma Payment Scheme (DMPS,
for if unable to find employer responsible or their insurer)
o Payments based on age of diagnosis; 2008 scheme provides single payment
o DMPS based on details of claim
Byssinosis
Inhalation of cotton particles; Symptoms typically start on first day back at work
after break (“Monday Sickness”) – Chest Tightness, Cough, SOB
o Possible Aetiology via Bacterial Endotoxins in raw cotton
o Pure cotton does not cause disease; Cotton dust has effect on Airflow Limitation;
Individuals with Asthma particularly badly affected
Berylliosis
Inhalation of Beryl causes systemic illness similar to clinical picture of Sarcoidosis
o Clinically presents as Progressive Dyspnoea with Pulmonary Fibrosis
o Rare after regulations on working atmosphere in aerospace and electronics industries
