silicosis is a type of occupational lung diseases

1. National University, Sudan
Faculty Of Medicine - Batch 9
2015-2016

2. Silicosis
• It is caused by inhalation of dust containing
free silica or silicon dioxide
• The incidence of silicosis depends upon
 The chemical composition of the dust
Size of the particles
Duration of exposure
Individual susceptibility

3. Types of Silicosis
• Chronic silicosis
- After 10 or more years of exposure
• Accelerated silicosis
- After 5 to 10 years of exposure
• Acute silicosis
- After weeks or months of exposure

4. Workers at risk in
• Mining Industries
• Pottery and Ceramic Industries
• Iron and Steel Industries
• Metal Grinding
• Sand blasting
• Building and Construction workers
• Glass manufacture
• Others

5. Pathogenesis
• After inhalation of the particles it interact with
the epithelial cell and are ingested by
macrophages which cause the activation and
release of mediators inducing an
inflammation, fluid accumulation and tissue
fibrosis
• Silicosis is characterized by a dense ‘’nodular’’
fibrosis in the upper zones of the lungs

7. Clinical Features
• Irritated cough
• Dyspnoea on exertion
• Chest pain
Investigation
• Chest X – ray : fine nodularity in the upper
zones of the lung
• Pulmonary function test
• Test for tuberculosis

8. Treatment
• Removing the source of silica exposure
• Supportive treatment
• Antibiotics or anti-TB drugs (if needed)
• Patients with severe silicosis may need to have
a lung transplant.