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Asthma

Pathophysiology of Asthma

Bronchospasm

Bronchial hyperresponsiveness (BHR)

Inflammation

Eosinophile activation

Epithelial destruction

Glandular destruction

Collagen deposition

Asthma Symptoms

Cough and/or

Wheeze and/or

Shortness of breath or chest tightness

Asthma is Inherited

· Atopic diseases

Allergic rhinitis

Atopic dermatitis

A child with one atopic disease is at threefold risk of developing at least one of the others

Eosinophile Activation

· Activation via IL5

· Increase longevity

· Hypodense and harder to kill

· Prevented by high dose corticosteroids

Mechanisms of Asthma

· Genetic disease

· CD4(2) cell medicated

· Eosinophil/macrophage induced inflammation

· Viral LRI (RSV): as many as 50% will have recurrent wheezing

· Smoking (active or passive)

· Allergens (especially cat, dog, and house dust mite)

· The disease is CD4(2) cell mediated

· Eosinophil/macrophage induced inflammation

Asthma: Triggers

· Viral UR/LRI causes increased bronchial hyperresponsiveness

· Exercise: Symptoms usually occur a few min after beginning exercise and resolve 20 min after