Autoimmune Disorders: Hypersensitivity Flashcards
What causes hypersensitivity disorders?
Exaggerated or inappropriate immune response
What is an allergen?
allergic response to an antigen
Tissue destruction: immune response vs. allergen
Tissue destruction from an immune response is more than what it would be from an allergen
How many general categories and types of hypersensitivity disorders are there?
- 2 general categories
- 4 types
What are the categories of hypersensitivity disorders based upon?
rapidity of immune response
What are the categories of hypersensitivity disorders?
- immediate
- delayed
What are the types of hypersensitivity disorders?
I-IV
Hypersensitivity Type I
allergies
Hypersensitivity Type II
cytolytic or cytotoxic
Hypersensitivity Type III
immune complex
Hypersensitivity Type IV
cell mediated or delayed
Hypersensitivity Type I (allergies) clinical s/s
- varies
- ask client about their specifics
Hypersensitivity Type I: What is an allergy?
abn hypersensitivity from allergen introduction to body
Hypersensitivity Type I: How does the body fight allergies?
produces a special antibody immunoglobulin E (IgE)
antibody immunoglobulin E (IgE) breaks down these:
- mast cells
- mast cell mediators (histamine)
What is atopy?
genetic predisposition to produce large quantities of IgE
What is the result of large quantities of IgE?
results in development of typical s/s of allergies
What is anaphylaxis?
systemic manifestation of immediate hypersensitivity
What are the results of activation and breakdown of mast cells?
- vasodilation
- increased capillary permeability
- fluid loss into interstitial space
Clinical presentation of anaphylaxis
- bronchospasms
- hives
- anaphylactic shock
These s/s of anaphylaxis require immediate emergency response
- vocal hoarseness
- difficulty breathing
- chest discomfort
What are the causes of Hypersensitivity Type II (cytolytic or cytotoxic) disorders?
- production of autoantibodies against self cells that have a foreign protein attached
- autoantibody binds to altered self cells
The complex of autoantibodies that binds to altered self cells in hypersensitivity type II disorders is destroyed by the
immune system
What are some examples of Hypersensitivity Type II disorders?
- anemia
- idiopathic thrombocytopenic purpura (ITP)
- hemolytic disease in newborns
Clinical s/s of Hypersensitivity Type II disorders
- HA
- flank pain
- chest pain
- N/V
- tachycardia and hypotension
- hematuria
- urticaria
What is urticaria?
hives
What is the cause of Hypersensitivity Type III disorders?
formation or deposition of ANTIGEN-ANTIBODY COMPLEXES in tissues
Examples of Hypersensitivity Type III disorders
- RA
- serum sickness
Clinical s/s of Hypersensitivity Type III disorders
- fever
- arthralgias
- synovitis
- lymphadenopathy
- urticaria
- visceral inflammation
When do hypersensitivity type IV (cell mediated or delayed) occur?
24-72 hours after allergen exposure
Examples of hypersensitivity type IV disorders
- injection of TB antigen
- graft vs. host disease
- transplant rejection
- contact dermatitis
Clinical s/s of hypersensitivity type IV disorders
- itching
- erythema
- vesicular skin lesions
