SPECIAL SELECTED TOPICS- RESPIRATORY SYSTEM DISORDERS-SSTRSDO-QAA 017

 Describe the main characteristics of silicosis.

Silicosis is a chronic fibrosing lung disease caused by prolonged inhalation of crystalline silica dust, commonly encountered in mining, quarrying, sandblasting, and stone cutting. Silica particles are ingested by alveolar macrophages, leading to their activation and death with release of fibrogenic cytokines.

The lungs develop multiple small, firm silicotic nodules composed of concentric layers of collagen. The upper lobes are predominantly affected. Progressive fibrosis reduces lung compliance and causes restrictive lung disease.

Patients present with chronic cough, exertional dyspnea, and reduced exercise tolerance. Silicosis increases susceptibility to pulmonary tuberculosis because silica impairs macrophage function.

Advanced disease may progress to progressive massive fibrosis, pulmonary hypertension, and respiratory failure. Prevention depends on reducing occupational silica exposure and using appropriate respiratory protection.

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DR.C.GANESAN M.D

PROFESSOR OF MEDICINE