Allergy Flashcards
What is an allergy?
aka as hypersensitivity - its an extreme immune reaction to a harmless antigen (aka an allergen)
4 types of Hypersensitivity:
Type I: Immediate
Type II: cytotoxic
Type III: immune-complex
Type IV: Delayed
What is the most common type of allergy + what is it?
type I, it’s an immediate rapid local response to allergen, caused by IgE which releases histamines = allergy symptoms like edema, congestion, irritation, welts, and itching of hives.
What is anaphylaxis = what can cause it/
life threatening acute, systmic, allergic reaction that can be caused by latex, peanuts, penicillin, and venom of stinging insects such as wasps and bees
What are the signs and symptoms of anaphylaxis?
sudden drop in bp, rapid and weak pulse, nausea, vomiting, narrowing of airways
What is used to treat anaphylaxis?
corticosteriods, epinephrine and antihistamines
What is Type II hypersensitivty?
aka as cytotoxic bc IgM or IgG = destruction of cells
Example of cytotoxic hypersensitivty
incompatible blood transfusion (person w/ A blood gives blood to person with B blood which = antibodies interact with antigens in trasnfused RBC which cause them to agglutiante and lyse)
What is Type III hypersensitivty?
aka immune-complex hypersensitivity - antigens combine with antibodies = soluble mass called immune complexes that deposit in tissues and bv where they trigger inflammation
Example of immune complex hypersensitivty?
After a streptococcal infection,
immune complexes composed of streptococcal
antigens and antibodies might form in the kidneys, where they cause the inflammatory disease
glomerulonephritis
What is Type IV hypersensitivity?
delayed hypersensitivty bc it takes time to develop due to t cells needing time to recognize allergen and bring allergy symptoms
examples of type IV hypersensitivty/
skin reaction to poison ivy, poison oak, contanct dermatitis from wearing latex gloves and the tuberculosis skin tests
most common allergy test?
skin test where suspected allergen in placed on or below skin to assess skin’s response to allergen
other types of allergen test?
skin prick, intradermal test and skin patch test
What is desensitization of allergy?
take allergy shots of a little of the allergen so the body can build up resistence