24. Pulmonary infections Chronic 3 - Cox

• TB - pathogenesis

  1. infects macrophage by receptor mediated endocytosis
  2. Block fusion of phagosome and lysosome - preventing intracellular destruction
  3. replicate within phagosome
• TB pathogenesis after infection

  1. macrophage with TB will drain via lymph node
  2. APC macrophages activate Th1 cells
  3. activate INFy
  4. macrophage will try to kill TB but granuloma will form due to impair clearance
• Primary TB will develop in naive individual

  • typically involve mid lobes
• Secondary TB

  • cavitary
  • likes upper lobes
  • increase O2 tension due to decrease pulmonary perfusion
  • increase growth
• What kind of people infected with TB does not form granuloma?

  IC pts