Chapter 16 Part 1 Flashcards
What are the four types of hypersensitivity reactions?
I- Immediate hypersensitivity
II- Antibody-mediated
III- Immune complex-mediated
IV- T Cell mediated
What type of hypersensitivity is considered immediate and involves IgE?
Type I
What type of hypersensitivity is antibody-mediated, involves IgG, and complement?
Type II
What hypersensitivity involves IgG and immune complexes?
Type III
What hypersensitivity is considered delayed and involves T cells?
Type IV
What is an allergy? How do allergies manifest?
A condition of altered reactivity or exaggerated immune response that is manifest by inflammation
What is Atopy? Anaphylaxis?
Atopy- local allergy
Anaphylaxis- systemic reaction
What is a sensitizing dose?
The initial exposure or the first time a person is exposed to the antigen
What is produced by the body’s immune system (third line), following a sensitizing dose?
Memory cells and antibodies
Why do some individuals appear to react upon forts exposure to an antigen/allergen?
They were exposed prior and were unaware
How does IgE interact with mast cells and basophils during an allergic reaction?
They are triggered by the IgE to release chemicals which trigger inflammatory responses
What causes the symptoms of an allergy?
Hystomines
What are the four characteristics of mast cells and basophils?
1) ubiquitous in tissues
2) capacity to bind IgE during sensitization
3) contain secretory vesicles which contain physiologically active cytokines
4) have a tendency to degranulate
What is hay fever (allergic rhinitis)?
A generic term for allergic rhinitis, a seasonal reaction to inhaled plant pollen
Asthma is characterized by impaired breathing due to severe _____________.
Bronchoconstriction
What makes asthma suffers different from people with typical allergies?
They are highly responsive to minute amount of inhalant allergens, food, or other stimuli.
What is atopic dermatitis?
Intense itchy inflammatory condition of the skin
What parts of the body do food allergies primarily affect? Be able to list at least three of the most common food allergens.
Respiratory tract, skin, gastrointestinal
Common food allergies:
Peanuts, cow’s milk, eggs
What is the most common drug allergy?
Penicillin
What is the difference between a cutaneous and a systemic anaphylactic reaction?
Cutaneous- inflammation that is local (small bumps like hives)
Systemic- sudden respiratory and circulatory disruption that can be fatal in as little as a few minutes
What reaction is referred to as the “wheel and flare reaction”?
Cutaneous
