Hypersensitivity Flashcards
Hypersensitivity
HEIGHTENED STATE of immune response and an EXAGERRATED response to a harmless antigen that results in injury to the tissue, inflammation, cell destruction, or even lead to death
Immediate specific hypersensitivity reaction mediated by IgE antibodies
ATOPY
Atopic allergies
Fever
Asthma
Food allergies
Latex sensitivity
Altered reaction to external substances that results to an exaggerated response reacting strongly to allergens
Allergy
Allergens
Antigens of Low MW that cause allergic reaction to occur
Type I Hypersensitivity Reaction
Anaphylactic or Immediate Hypersensitivity Reaction
Type II Hypersensitivity Reaction
Cytotoxic
Type III Hypersensitivity Reaction
Immune Complex
Type IV Hypersensitivity Reaction
T cell dependent (Cell Mediated)
Severe type of hypersensitivity reaction that simultaneously involves multiple organs (systemic response) leading to death.
ANAPHYLAXIS
True or False. Morse. IMMEDIATE HYPERSENSITIVITY develop within minutes to hours. Triggers the formation of IgG and IgM
First statement is true. Second statement is false.
A: Triggers the formation of IgE
It causes anaphylactic reaction (systemic response)
Type I Hypersensitivity Reaction
Major mediators of Type 1 Hypersensitivity Reaction
Histamine
leukotriene C4
interleukin-4 (IL-4),
interleukin-13 (IL-13)
IgE mediated
Type I
Effector Cells for IgE
Mast cells/Basophils
Mechanism in Type I Hypersensitivity Reaction
People with IgE antibodies on particular allergen that developed when the body detected as foreign by the interaction of the mast cells to the IgE releasing mediators which becomes cells to be sensitized and react aggressively once exposed on the same allergen.
3 Stages of Anaphylaxis
- Allergen attaches to the IgE antibody fixed to the surface membrane of mast cells and basophils.
- Sensitized mast cells and basophils release various mediators.
- Mediators affect to produce vascular changes and activation of platelets, eosinophils, neutrophils, and the coagulation cascade.
Signs and Symptoms of Allergic reactions
bronchospasm and laryngeal edema vascular congestion skin manifestations (urticaria: hives) angioedema diarrhea or vomiting, Intractable shock
a.k.a Anaphylaxis like or Pseudo-anaphylaxis
Anaphylactoid Reaction
True or False (Morse). Anaphylactoid Reaction is the result from immunologically inert materials that activate serum and tissue proteases and the COMMON PATHWAY of Complement system. It is mediated by Antigen-Antibody reaction.
Both Statement are not True.
A: It results from activation of the ALTERNATIVE pathway of the complement system.
A: Not mediated by Antigen-Antibody
In vivo tests for Type I Hypersensitivity reaction
Skin puncture Test (SPT)
In vitro tests for Type I Hypersensitivity reaction
Total IgE
Competitive radioimmunosorbent test (RIST)
Radio allergosorbent Test or March Profile
Chemiluminescent Enzyme Immunoassay
All are not in vivo test; except
- SPT
- RIST
- Chemiluminescence
- March Profile
SPT
Used radiolabeled IgE to compete with patient IgE for binding sites on a solid phase coated with anti-IgE
RIST
This includes Localized Reactions
Urticaria
Angioedema
Skin reactions
5 Cardinal Signs
Dolor Rubor (Redness) Pallor (Paleness) Calor (Pain) Functio leisa (Loss of Function
Antobodies involved in Type II Hypersensitivity reaction
IgG and IgM
For how many minutes which SPT is observed after inoculation
15 minutes
What are observed after SPT
Redness
Inflammation
Spots
Diameter (>3 mm)