NEET PG High-Yield: Silicosis
Silicosis is a chronic, progressive, and incurable fibrotic lung disease caused by the inhalation of free crystalline silica ($SiO_2$) dust. It remains a top-priority occupational lung disease for NEET PG exam preparation.
Key Clinical & Radiographic Findings
- Pathophysiology: Silica particles reach the alveoli, are ingested by macrophages, inducing cell death and stimulating collagen deposition (fibrosis).
- Chest X-ray (CXR): Characteristic “Snowstorm appearance” (small, rounded opacities) primarily in the upper lobes.
- Lymph Nodes: “Eggshell calcification” of hilar lymph nodes is a hallmark, pathognomonic finding.
- Clinical Association: Significantly increased susceptibility to Tuberculosis (Silico-tuberculosis).
High-Risk Occupations
| Industry | Activity |
|---|---|
| Mining | Gold, coal, and lead-zinc mining. |
| Construction | Stone cutting, rock drilling, tunneling. |
| Manufacturing | Ceramics, glass, foundry work, sandblasting. |
High-Yield NEET PG Pearls:
- Prevention: Wet drilling is the most effective engineering control to suppress dust.
- Lung Function: Typically shows a restrictive pattern on spirometry.
- Comparison: Unlike Asbestosis (which typically affects the lower lobes), Silicosis is an upper-lobe predominant disease.
- Screening: Every patient with suspected silicosis must be screened for active tuberculosis due to the high co-morbidity.