University:
Western Sydney University
Course:
MEDI 2003 | Clinical Sciences 2
Academic year:

2024
Views:

114

Pages:

2
Author:

Mariam A. A.

Chronic inflammation of respo passage mucosa → difficult to breathe Atopic Triad asthma allergic rhinitis atopic dermatitis Samlter’s Triad Asthma Nasal Polyps A.A. → Aspirin sensitivity COX Lipo-oxygenase P.G. leukotriene LTc4 LTd4 LTC4 LTD4 broncho spasm mucus in airway ↑ vascular permeability Others Dust Pet hair Smoke exercise cold viral URI Beta 2 Blockers cold & dry air → initiation Hygiene hypothesis (late onset) ↑ WBC maturation Allergen ↓ Dendritic cells or macrophages ↓ Phagocytosis ↓ Phagolysosome ↓ Express antigen on MHC II ↓ Lymph Nodes IL-2 ↓ IL-4 → IL-4 & IL-5 → Plasma cells ↓ ↑↑ IgE IL-6 → CO29+ IL-9 → G → IL-2 → IL-4 T-R B7 → CD28+ → IL-1 ↓ CO-stg IL-4 → IL-13 Histamine Leukotrienes Bronchioles submucosal & mucosa ↓ inflamed mucosa vascular permeability ↑ eosinophil infiltrate inflammatory exudate degranulation ↑Fcε mast cell Histamine Leukotrienes on respo S.M. constriction Proteases (Chronic) Bronchospasm ↑ [Ca2+] PLC ↑ → DAG → ER ⇆ IP3 ↑ PIP2 ↑ → PLC → Gαq → Histamine → H1-R → bronchioles Ca2+ ↑ Presynaptic vasoconstriction tone SNS nerve terminals ↑ GTP ↑ → H1-R → NO → sGC → GTP → cGMP → Ca2+ GTP → H2R goblet cells → H2R → mucin goblet cells H2R → mucin obstruction ↓ FEV1, FVC The pleural pressure squeezes on airways in expiration air trapping hyper-resonance ↓ venous return in inspiration venous return ↓ ↑ pressure ↑ alveoli V → ↓ Po2 ↑ Pco2 dyspnoea force against productive cough bronchioles ↑ diameter ↑ resistance airway remodelling collagen deposition ↑ IL-13 ↑ mucus airway obstruction irreversable → fibrotic chronic Astestis remodelling → narrowed air way → acute → narrowed air way expiratory wheeze turbulent air flow narrow airways obstruction chest tightness forceful use of expirational m.