16. Pneumoconioses

• Pneumoconiosis

  • Caused by inhalation of certain primarily inorganic dusts and lung tissue reaction
  • main cause is from chronic work place exposure
• Coal worker's pneumoconiosis (CWP) - carbon pigment accumulates in macrophages (anthracotic pigment)
• Coal worker’s pneumoconiosis (CWP) may progress even if dust exposure ceases
• Caplan's syndrome - combination of pneumoconiosis + rheumatoid arthritis
• Caplan lesion: central necrosis surrounded by

  • collagen
  • fibroblasts
  • macrophages
• Silicosis is due to inhalation of crystalline silicon dioxide
• Classic silicosis

  • silica directly toxic to cells
  • tissue damage occur via ROS damage
  • macrophage release TNF --> stimulate fibrosis
• Classic silicosis nodules - more collagenous with time
• Silica can damage and impair macrophage function

  • increasing risk of TB
• Classic silicosis involve hilar lymph nodes and pleura

  • eggshell calcification
• beryllium dust can lead to multisystem granulomatous disease
• acute beryllium disease has similar manifestation to ARDS
• Asbestos related disease occupations?

  • shipbuilding
  • maritime activities
• Asbestosis - macrophage will attempt to engulf and fail to digest asbestos fiber

  • release ROS which will lead to fibrosis