Pneumoconiosis
“dust diseases” – non neoplastic reaction of lungs to inhaled mineral or organic dust
The reaction of the lung depends on:
- Properties of dust – fibrogenic vs. inert
- Size of inspired particles
- Length of exposure
- Individual susceptibility of host
Inert dusts → interstitial aggregates of dust-filled macrophages (DUST MACULE)
Fibrogenic dusts → hyaline nodules or stellate areas of fibrosis, peribronchiolar fibrosis, diffuse interstitial fibrosis +/- granulomas and large fibrous or cavitary masses (PROGRESSIVE MASSIVE FIBROSIS).
| Histological reaction | Aetiological dusts |
| Dust macule | Coal dust (uncomplicated coal-worker’s pneumoconiosis)Iron (siderosis) |
| Concentric hyaline nodules | Silica (nodular silicosis) |
| Stellate interstitial fibrosis | Silica + inert dust (mixed dust pneumoconiosis) |
| Diffuse interstitial fibrosis | Silica (complicated silicosis) +/- other fibrogenic dust |
| Peribronchiolar fibrosis | Asbestos |
| Granulomas | Beryllium (berylliosis)Talc (talc pneumoconiosis) |