Feline Asthma Syndrome

• Synonym: feline allergic bronchitis
• Pathology very similar to COPD/SPA-RAO in horses and human asthma, although few published papers relating to it
• Allergens - house dust mites, fungal spores
• Widespread narrowing of airways
  • Extrinsic asthma
    • Type I hypersensitivity in response to allergen challenge - mediated by IgE
    • Pathological changes:
      • Exudate into airways - mucus/ cells
      • Thickened airway walls - oedema, glandular and smooth muscle hypertrophy, vascular congestion
      • Altered fluidity of mucus (associated with goblet cell hyperplasia) -> less effective mucociliary apparatus
  • Intrinsic asthma
    • A proportion of cats there is an increased propensity for the bronchial smooth muscle to contract (increased bronchial reactivity) -> airway constriction