Asthma and Atopy

Question 0

Asthma is characterized by (5) Sx

Answer 0

Paroxysmal or persistent Sx of:
Dyspnea
Chest tightness
Wheezing
Sputum production
Cough

Question 1

Prevalence of asthma in Canada? Increasing or decreasing in last 15 years?

Answer 1

10-20%, increased 4 fold in children under 15 in the last 15 years
Most common chronic childhood illness

Question 2

Asthma Dx in children <6 years is based on ……

Answer 2

History and physical ….PFTs not feasible!

Question 3

Bronchiolitis

Answer 3

In infants less than 2 years
Less than 3 episodes of wheezing
NOT managed the same as asthma

Question 4

Describe Episodic viral wheeze (EVW)

Answer 4

Aka. Intermittent virally induced asthma
Toddler and preschool years
Wheezing ONLY with resp infections
No asthma Sx between episodes
No fam Hx asthma, no atopy
Resolves towards school age

Question 5

Describe classic asthma

Answer 5

Aka. Persistent asthma
Increasing prevalence through childhood
Airway hypersensitivity with variable airway obstruction
Fam Hx atopy
Chronic bronchial inflammation

Question 6

Major and minor risk factors for asthma

Answer 6

Major: parental Hx asthma, eczema
Minor: eosinophilia, wheezing without colds, allergic rhinitis

Question 7

Atopic triad

Answer 7

Eczema
Asthma
Allergic rhinitis/hay fever

Question 8

Most common type of hypersensitivity rxn? Mediated by which Ig?

Answer 8

Type 1

Mediated by IgE

Question 9

Describe oral allergy syndrome

Answer 9

Usually seen in hay fever sufferers
Sx usually localized in mouth/throat
True allergy to certain fruits, nuts, vegetables
Cross reactivity between pollen and fruit proteins
Allergic rxns occur only with raw food

Question 10

Birch pollen allergy is associated with which fruits in oral allergy syndrome

Answer 10

Apple, peach, plum, pear, cherry, apricot

Also: almonds

Question 11

How does epinephrine work in anaphylaxis?

Answer 11

Non selective agonist of ALL adrenergic receptors
For anaphylaxis, we are particularly concerned with alpha 1, beta 1 and beta 2 adrenergic receptors
Increase peripheral vascular resistance by promoting vasoconstriction (alpha 1)
Reduces angioedema (alpha 1)
Increased inotropic and chronotropic effects (beta 1)
Bronchodilation (beta 2)
Decreased release of inflammatory mediators from mast cells and basophils (beta 2)

Question 12

List four ways to Dx allergies

Answer 12

Prick skin tests
Serum specific IgE production
Food challenge
Metacholine/inhalant allergen challenge

Question 13

Poison ivy usually elicits which kind of hypersensitivity rxn?

Answer 13

Type IV => contact dermatitis based on direct exposure

Intercellular edema of the epidermis