Flashcards in Lecture 16 - Type I hypersensitivity - ALLERGY Deck (39)
What is the most important aspect at arriving at a correct diagnosis for IgE allergic reactions?
How else can allergic responses be detected?
A careful clinical history is the most important factor in arriving at the
correct diagnosis!!!! (TEST)
1. Skin testing and measuring specific IgE:
b) In vitro assays (BUT ONLY USED IN DIAGNOSTIC ADJUNCTS TO AN APPROPRIATE CLINICAL SETTING)
c) skin testing and RAST can be positive, but the patient may NOT have the clinical symptoms
What are 4 types of treatment options of Allergic Reactions?
1. Allergen avoidance
2. Anti-IgE therapy
- use of monoclonal anti-IgE antibody to bind to site on circulating IgE that binds to cell bound IgE receptor
3. Allergen Immunotherapy
- promote either Th1 or TH2 response
- subcutaneous, sublingual, or oral route
How does Anti-IgE therapy done?
What does it decrease?
Anti-IgE therapy-use of an anti-IgE monoclonal antibody that has been
engineered to bind to the site on circulating IgE that binds to the cellbound
Anti-IgE therapy results in decrease in eosinophilic
inflammation and IgE-bearing cells.
Withdrawal of this therapy results in
return on asthma symptoms and this correlates with increasing serum IgE.
Why does the delayed reason occur?
Most likely due to recruitment of Eosinophils
What happens during allergic anaphylactic shock?
HYPOVOLEMIA (drop in BP)
- increase in HR
TX: with epinephrine injection
What factors of the environment increase allergen sensitivity?
What about T cells?
What are the 3 triggers?
1. RIGHT ALLERGEN AT THE RIGHT TIME
2. SMALL FAMILY
4. ANTIBIOTICS EARLY
What is the in vivo and in vitro allergen testing?
1. Vivo - Skin testing
2. Vitro - RAST
What are the steps for RAST?
1. Allergen in solid phase
2. Patient IgE serum
- patients serum added to cellulose disc with covalently bound ALLERGENS
3. IgE binds allergen
4. After washing, radio-labeled Anti-IgE added
- radioactivity is counter with a gamma counter