Pneumoconiosis

Abstract

Occupational lung diseases cover the whole range of respiratory illnesses: diseases of the parenchyma with fibrosis such as silicosis and asbestosis; diseases of the airways such as occupational asthma, asthma-like syndrome and chronic obstructive lung disease diseases; diseases of the pleura such as diffuse pleural fibrosis due to asbestos exposure, and occupational cancers. The clinical features of diffuse lung fibrosis due to asbestos are not much different from idiopathic pulmonary fibrosis; those of occupational asthma are not different from those of common asthma and the same for lung cancer. The only important clue to the diagnosis is the history of exposure, which many of us often fail to elicit. Yet it is important to recognise occupational exposure as the cause of the disease for two reasons: removal from exposure if the disease is diagnosed early may lead to a cure at least in the case of occupational asthma and in some countries, workers' compensation board or similar agencies offer financial assistance and rehabilitation to these patients. Patients with occupational lung diseases are often difficult to manage since treatment usually consists of removal from exposure. Even in developed countries where social securities are reasonably good, patients with occupational lung diseases suffer financially and their quality of life impaired after the diagnosis. In developing countries, it is often not possible to remove the patient from exposure without taking away their livelihood and those of their families. These patients very often do not wish their employers to learn of their illness nor do they wish their disease to be reported to the workers'compensation boards or similar agencies. Busy physicians may not wish to deal with the hassle of submitting a claim for patients with occupational lung disease. Thus occupational lung diseases are often not reported even though they are notifiable diseases in many countries. It is not easy to obtain good data on the incidence of occupational lung disease through medicolegal statistics or registries or from any source. During the past two to three decades, there has been a change in the pattern of occupational lung diseases in developed countries. With better recognition and understanding of the disease process, and better exposure control, pneumoconiosis is gradually decreasing while occupational asthma has become the most prevalent occupational lung disease. However, this is not true in developing countries where pneumoconiosis is still very prevalent due to poor working conditions, inadequate control of exposure, and in most cases, lack of worker education on safety issues and recognition of hazardous products. Within the limited scope of this chapter, common conditions will be discussed only. © 2005 Hong Kong University Press, HKU. All righrts reserved.