Asthma Types?
Extrinsic and Intrinsic
Extrinsic asthma associated with?
Associated with type I hypersensitivity reaction; IgE mediated; triggered by allergens
Extrinsic asthma seen in?
seen in children
Intrinsic asthma associated with?
Associated with chronic bronchitis; triggered by respiratory viral infections, environmental pollutants exercise, or cold
Intrinsic asthma seen in?
seen in adults
pathogenesis of asthma? (early phase reaction)
Early phase reaction:
- Type 1 Hypersensitivity of bronchial airways results in
- induction of TH2 cells
- which secrete a variety of cytokines
- results in
bronchoconstriction & mucus secretion
pathogenesis of asthma? (late phase reaction)
- recruitment of leukocytes
- which secrete more factors & cytokines
- to cause another bout of epithelial damage and airway narrowing
Airway remodeling in asthma?
- repeated bouts of allergic asthma result in structural changes of the bronchial wall
- Hypertrophy of bronchial smooth muscle;
- hyperplasia of bronchial submucosal glands;
Asthma gross fx?
- Mucosal & submucosal edema
- Leukocytic infiltrate (eosinophils, mast cells, lymphocytes)
- Epithelial cell necrosis
- Bronchial wall fibrosis
Histology of sputum in asthma?
mucous plugs containing
- Curshmann spirals
- Charcot-Leyden crystals
- Creola bodies
Asthma clinical signs?
Dyspnea; expiratory wheezing; cough; use of accessory muscles of respiration; pulsus paradoxus
Asthma Complications?
Status asthmaticus (prolonged asthma attack)
Asthma Lab findings?
Hypoxia,
decreased FEV1/FVC ratio,
eosinophilia in children
Asthma Treatment Quick Relief?
Inhaled β2-adrenergic agonists (salbutamol) for quick relief;
Asthma Treatment long-term control?
Inhaled or systemic corticosteroids, leukotriene pathway inhibitors, cromolyn, or theophylline for long-term control
