Silicosis
Silicosis is a fibrotic occupational lung disease caused by inhaling crystalline silica dust, producing upper-zone nodular opacities and progressive dyspnea in exposed workers. Diagnosis rests on a compatible exposure history plus a characteristic imaging pattern. No agent reverses the fibrosis, so management is supportive: exposure cessation, oxygen for hypoxemia, vaccination, isoniazid prophylaxis for latent tuberculosis, and transplant evaluation for advanced disease.
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What this article covers
- Overview
Definition: Silicosis is a fibrotic occupational lung disease caused by inhaling respirable crystalline silica dust, producing a spectrum from asymptomatic nodular disease to severe, disabling fibrosis.
- Epidemiology
Typical patient: A man in a silica-exposed trade, mining, quarrying, sandblasting, foundry work, stone or countertop fabrication, ceramics or glass manufacture, or hydraulic fracturing for natural…
- Risk factors
High-silica trades: Sandblasting, underground and surface mining, quarrying, stone or engineered-countertop cutting, foundry and ceramics work, glass manufacture, and sand handling for hydraulic fracturing.
- Pathophysiology
Initial injury: Respirable crystalline silica particles reach the distal airways and are phagocytosed by alveolar macrophages.
- Clinical features
Chronic simple silicosis: Often asymptomatic or mild dyspnea and cough, discovered incidentally on a screening or unrelated chest radiograph after a long exposure history.
- Differential diagnosis
Coal workers' pneumoconiosis: Similar upper-zone nodular pattern, but the history is underground coal mining without substantial silica exposure, unlike the silica-specific trades in silicosis.
- Diagnosis
What establishes the diagnosis: Silicosis is established by a compatible occupational silica-exposure history together with a characteristic radiographic pattern, bilateral upper-zone small rounded…
- Management
First action: Remove the patient from further silica exposure and counsel smoking cessation; this is the single intervention shown to slow decline, because no agent reverses established fibrosis.
- Complications
Progressive massive fibrosis: Coalescing nodules produce irreversible restrictive physiology with a falling diffusing capacity and, over years, respiratory failure.
- Prognosis
Chronic simple silicosis: Often stable or slowly progressive, particularly once exposure stops, with near-normal life expectancy in many patients.
- Prevention
Engineering controls: Wet cutting, local exhaust ventilation, and enclosed processes reduce airborne respirable silica at the source, the primary prevention strategy in high-risk trades.
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