Coal worker’s pneumoconiosis (CWP)

• What is Coal Worker’s Pneumoconiosis (CWP)
• Statistics on Coal Worker’s Pneumoconiosis (CWP)
• Risk Factors for Coal Worker’s Pneumoconiosis (CWP)
• Progression of Coal Worker’s Pneumoconiosis (CWP)
• Symptoms of Coal Worker’s Pneumoconiosis (CWP)
• Clinical Examination of Coal Worker’s Pneumoconiosis (CWP)
• How is Coal Worker’s Pneumoconiosis (CWP) Diagnosed?
• Prognosis of Coal Worker’s Pneumoconiosis (CWP)
• How is Coal Worker’s Pneumoconiosis (CWP) Treated?
• Coal Worker’s Pneumoconiosis (CWP) References

What is Coal Worker’s Pneumoconiosis (CWP)

Coal Worker’s Pneumoconiosis (CWP) is a disease of the lung resulting from the long-term inhalation of microscopic dust particles which was most commonly seen in coal worker’s, hence the name. CWP affects the small airways and alveoli of the lung, particularly in the upper zones.
Simple CWP (without the presence of Progressive Massive Fibrosis (PMF), Caplan’s syndrome, bronchitis or emphysema) is an asymptomatic (symptomless) disease with no effect on life expectancy. Severe disease with the onset of significant lung fibrosis or emphysema is much more severe and can progress to cause pulmonary hypertension and right heart failure, the prognosis will vary on the severity of complications.

Statistics on Coal Worker’s Pneumoconiosis (CWP)

Coal Worker’s Pneumoconiosis forms a part of the group of disorders called the occupational lung diseases. In Australia 6% of the deaths from occupational lung disease is due to CWP. The number of cases of CWP is reducing due to better methods of prevention. CWP is the leading cause of death due to occupational lung disease in America.

Risk Factors for Coal Worker’s Pneumoconiosis (CWP)

Coal dust exposure is the primary causative factor for the development of CWP. The length and magnitude of exposure determine the rate of progression. Dust composition and combustibility can affect the nature and severity of the reaction. Workplace conditions, such as coal-face proximity, ventilation and dust suppression are important causative factors.

Progression of Coal Worker’s Pneumoconiosis (CWP)

On average it take 20 years of exposure to coal dust for CWP to develop. Usually CWP causes little or no decline in lung function. If there is development of progressive massive fibrosis however there is severe decline in respiratory function, and can cause right Heart Failure. There is some evidence that coal dust exposure can lead to an increase in chronic obstructive pulmonary disease (COPD), however there is no evidence to show that CWP in non-smokers causes a greater risk of cancer, and there is even evidence to suggest that it causes a reduced risk of lung cancer but a larger risk of adenocarcinoma of the stomach. The effects of CWP can be aggravated by the co-existence of other conditions such as rheumatoid arthritis, which can results in a condition known as Caplan’s syndrome.

Symptoms of Coal Worker’s Pneumoconiosis (CWP)

Patients with CWP are often symptomless. The patient with PMF will present with progressive shortness of breath, cough, blackened sputum (melanoptysis), respiratory failure
and cor pulmonale. Co-existing chronic bronchitis, emphysema and/or asthma is common.

Your doctor will take a thorough history which will include a detailed history of the patients working environment:

• Job type and activities: employer, what type of products the company produces, job title, years worked, description of job tasks or activities, description of all equipment and materials the patient uses, description of process changes and dates they occurred, and temporal associations between symptoms and days worked.
• Exposure estimate: visible dust or mist in the air and estimated visibility, dust on surfaces, visible dust in sputum (nasal drainage) at end of work shift, hours worked per day and days per week, an open or closed work process system, personal protective equipment used: type, training, fit testing, sick co-workers.
• Bystander exposures: job activities and materials used at surrounding work stations, timing of worksite cleaning (during or after shift), individual performing cleanup and process used (wet versus dry)

Clinical Examination of Coal Worker’s Pneumoconiosis (CWP)

Your doctor will perform a thorough examination of your respiratory system in order to find evidence of CWP or any of its complications.

How is Coal Worker’s Pneumoconiosis (CWP) Diagnosed?

Your doctor may order the following tests when investigating you for CWP:

• Chest x-ray this is to identify the number and location of the various lesions. This can enable the doctor to grade the severity of disease on a scale of 1 to 3.

 

• Full blood count – this can be used to rule out the possibility of underlying infection.
• Sputum culture – this is to identify any possible infection
• Pulmonary/Lung Function tests – the doctor may perform these tests to establish how badly the disease has affected lung function.
• CT – this is a more accurate way of identifying and localizing lesions, and can also be used to grade disease.
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  Prognosis of Coal Worker’s Pneumoconiosis (CWP)

  Simple CWP (without the presence of PMF, Caplan’s syndrome, bronchitis or emphysema) is an asymptomatic (symptomless) disease with no effect on life expectancy. Severe disease with the onset of significant lung fibrosis or emphysema is much more severe and can progress to cause pulmonary hypertension and right heart failure, the prognosis will vary on the severity of complications.

  How is Coal Worker’s Pneumoconiosis (CWP) Treated?

  • Prevention: preventing a disease is the best way to manage it, so your doctor may ask you to change your line of work or alter your working conditions.
  • Stop smoking

   

• Oxygen to improve the delivery of oxygen to the blood stream and improve symptoms of the disease.
• Vaccinations against influenza and pneumococcus: this is especially important because people with CWP are susceptible to infection, and should they develop an infection it can have potentially fatal effects on their lung function.
• Monitoring of disease with serial chest x-rays and CT scans – this is to ensure that the disease is not spreading and that there are no underlying complications developing.
• Treating complications of the disease which include: chronic obstructive pulmonary disease (COPD), asthma, and right heart failure.
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  Coal Worker’s Pneumoconiosis (CWP) References

  1. Beckett W.S. ‘Occupational respiratory diseases’, New England Journal of Medicine, 2000, vol. 342, no. 6, pp. 406 -413
• ‘Emedicine – Coal Worker’s Pneumoconiosis’ [online], Emedicine, Available at URL http://www.emedicine.com/med/topic398.htm (last accessed 23/03/2007)
• Finkelman R.B. et. al. ‘Health impacts of coal and coal use: possible solutions’, International Journal of Coal Geology, 2002, vol. 50, 425-443
• Fishwick D. Systemic and Parenchymal Lung Diseases. Medicine Publishing Company. 2004
• Glazer C.S. & Newman L.S. ‘Occupational interstitial lung disease’, Clinics in Chest Medicine, 2004, vol. 25, pp. 467-478
• ‘Harrisons Chapter 238-Environmental lung diseases-Coal workers pneumoconiosis’ [online], McGraw Hill’s AccessMedicine, Available at URL http://www.accessmedicine.com (last accessed 23/03/2007)
• Kumar P & Clark M. Clinical Medicine. 6th ed Edinburgh. WB Saunders 2006
• Kumar V et.al. Robbins Pathological Basis of Disease. 6th ed. Philadelphia. WB Saunders 1999
• Murray J. & Ross M. H, ‘Occupational respiratory disease in mining’, Occupational Medicine, 2004, vol. 54, no. 5, pp. 304-310
• Smith D. R. & Leggat P. A. ’24 years of pneumoconiosis mortality surveillance in Australia’, Journal of Occupational Health, 2006, vol. 48, no. 5, pp. 309-313
• Talley NJ & O’Connor S. Clinical Examination – A systematic guide to physical diagnosis. 4th ed. Sydney. MacLennan & Petty. 2001
• Verdon M.E. ‘Common clinical presentations of occupational lung diseases’, American Family Physician, 1995, vol. 52, no. 3, pp. 939-946