18. Hemorrhagic lung conditions

• Pulmonary Hemorrhage Triad

  • hemoptysis
  • anemia
  • air space opacities in imaging
• localized pulmonary hemorrhage will restrict to one lung region
• diffuse pulmonary hemorrhage & diffuse interstitial hemorrhage - bleeding into alveolar spaces
• Most common Diffuse pulmonary hemorrhage is?

  autoimmune disorder
• diffuse alveolar hemorrhage can lead to organizing pneumonia

  • there will be collagen deposition in small airways --> pulmonary fibrosis
• In diffuse alveolar hemorrhage

  • alveolar septum indicate vascular inflammation
  • hypercellular inflammatory infiltrate - composed of neutrophils
  • degranulation causing capillary injury and leakage of erythrocyte
• Idiopathic pulmonary hemosiderosis can cause diffuse alveolar hemorrhage

  • repeated alveolar bleeding will lead to pulmonary hemosiderosis and fibrosis
• Idiopathic pulmonary hemosiderosis usually occur in children under 10
• Goodpasture syndrome - can affect both lung and kidney
• good pasture syndrome is anti-glomerular basement membrane disease
• Good pasture syndrome involve glomerulonephritis with alveolar hemorrhage
• what would be deposited in good pasture syndrome?

  basement membrane deposition anti-GBM (anti-collagen IV) IgG antibodies
• good pasture later stage will result in?

  organizing pneumonia leading to interstitial fibrosis
• ANCA-associated vasculitis (AAV) pathophysiology - due to immune activation and damage

  • ANCA antigen - PR3 and MPO - will activate neutrophil
  • leading to vessel wall destruction
• Microscopic polyangiitis (MPA)

  • there is no granuloma
  • involve neutrophil infiltration and damage --> leukocytoclastic angiitis
  • medial fibrinoid necrosis --> fibrin extravasation
• Granulomatosis with polyangiitis (GPA) - necrotizing noncaseating granulomatous inflammation
• Granulomatosis with polyangiitis (GPA) - involve upper and lower respiratory tract

  • frequent pulmonary capillaries with hemorrhage
• Microscopic polyangiitis (MPA) involve small vessels

  • affect only lower respiratory tract
• Granulomatosis with polyangiitis (GPA)

  • micro progressives to micronecrosis
  • central necrosis with rim of macrophages

  
• Granulomatosis with polyangiitis (GPA) - present with?

  • diffuse alveolar hemorrhage
  • hemoptysis
• GPA - clinical presentation

  • saddle nose deformity due to necrosis of cartilage
  • subglottis stenosis - due to tracheal wall thickening
• Eosinophilic granulomatosis w/ polyangiitis (EGPA)

  • allergy - associated with asthma and eosinophil
• Eosinophilic granulomatosis w/ polyangiitis (EGPA) due to immune dysregulation

  • release of eotaxin3 release that attracts Eos
  • activated eosinophil will release cytotoxic granules