Occupational exposure to coal dust leads to Coal Worker’s Pneumoconiosis (CWP), which has enormous social, medical and economic importance of many countries in the world where coal mining is a major industry. About 10% of the workers in a coal mine are having Coal Worker’s Pneumoconiosis who are working in coal mine for more than 20 years, that can be diagnosed by simple X-ray and if more sophisticated equipment’s are used than it is much higher. The anthracite miners have more grave situation, they have more than 50% positive X-rays on plain radiography. The prevalence of Coal Worker’s Pneumoconiosis is much lower in bituminous mines and in US and most western nations the mines are of bitumen so Coal Worker’s Pneumoconiosis is less prevalent in those countries.
With prolonged exposure to coal dust for 15-20 years, small, rounded opacities similar to those of silicosis develop in Coal Worker’s Pneumoconiosis. Like in silicosis presence of small nodules in the lungs is not associated with significant problem (simple Coal Worker’s Pneumoconiosis). Almost all the symptoms of Coal Worker’s Pneumoconiosis are due to development of chronic bronchitis and COPD (chronic obstructive pulmonary disease) due to effect of coal dust on lung tissue. If the patient is a smoker it acts as additive in development of Coal Worker’s Pneumoconiosis.
In complicated coal worker’s pneumoconiosis the size of lung nodule in radiograph ranges from 1 cm to the size of entire lobe that is usually seen in the upper half of lung. Like in silicosis this condition can progress to progressive massive fibrosis (PMF), that causes deficient lung function and a high mortality.
Caplan’s syndrome is one of the complication of coal miners was first described in patients of coal worker’s pneumoconiosis and was subsequently found in silicosis. The symptoms of Caplan’s syndrome include seropositive rheumatoid arthritis with characteristic pneumoconiotic nodules.