Chapter 22 - Immune Function Excess: Hypersensitivity Flashcards
Types of Hypersensitivity Reactions
Type 1: Rapid
Type 2: Cytotoxic
Type 3: Immune Complex
Type 4: Delayed
Hypersensitivities/Allergies
Increased/excessive response to presence of antigen exposure.
Degree of rx ranges from: uncomfortable (itchy, water eyes, sneezing) to Life threatening (allergy asthma, anaphylaxis, bronchoconstriction circulatory collapse)
Type I reaction
Rapid Hypersensitivity Reaction AKA atopic allergy
- Most common type
- Some reactions occur only in areas of antigen exposure
- Caused by increased production of immunoglobulin E (IgE) antibody class
Rapid Hypersensitivity Reaction ….
may involve blood vessels and bronchiolar smooth muscle, causing blood vessel dilation, decreased cardiac output, bronchoconstriction = ANAPHYLAXIS
Anaphylaxis AKA…
anaphylactoid reaction
Allergic Rhinitis
AKA Hay fever
Triggered by rx to airborne allergens
*Type 1:Rapid
Allergic Rhinitis causes a release of what?
Histamine which will cause an increase in the Eosinophil count
Epipen concentration
1:1000
epipen dosage in mg and times to give…
0.3-0.5 mg
q10-15 mins for anaphlaxis
q20-4h for asthma
Which disease is often correlated with latex allergy?
Spina Bifida
A person with a latex allergy should also avoid these foods…
Avacados, bananas, kiwi, potatoes, papaya, tomatoes
Interventions for Type 1 Reactions
Avoidance Therapy
Drug Therapy
Types of Avoidance Therapy
Environmental changes
Pet interventions
Drug Therapies for Type 1 Rx
Decongestants Antihistamines (benydryl, zyrtec, claritin) Corticosteroids (prednisone) Mast Cell Stabilizers (chromalyn) Leukotrine antagonists (singulair) Complementary and alternative therapy Desensitization therapy (allergy shots)
Early Sx of Anaphylaxis
- First feelings of uneasiness, apprehension, weakness, impending doom.
- Pruritus(itching) and urticaria (hives)
- Erythema, sometimes angioedema of eyes, lips, tongue
Anaphylaxis (prolonged)
Distributive shock
histamine causes capillary leak, bronchoconstriction, mucosal edema, excess mucus secretion.
Causes congestion, rhinorrhea, dyspnea, increasing respiratory distress with audible wheezing.
Can be fatal
What most frequently causes anaphylactic reaction?
Drugs and dyes
*Iodine Dye
Interventions for Anaphylaxis
- Epipen or Twinject
- Assess respiratory function;establish airway
- CPR if needed
- Epinephrine
- Antihistamines (for Angioedema and urticaria)
- Oxygen
- Treat bronchospasm
- IV fluids
Latex Allergy
Type 1 hypersensitivity reaction
Protein found in natural latex rubber products is specific allergen
Allergen causes interaction with IgE
Incidence of latex allergy is increasing
Health care workers are more susceptible.
Type II Reaction
Cytotoxic
Body makes special autoantibodies directed against self cells that have some from of foreign protein attached them.
Examples of Cytotoxic Rx
Hemolytic Anemias
Throbocytopenic purpura
Hemolytic transfusion reactions
Goodpasture’s syndrome
Goodpasture’s syndrome
Antibodies attack lungs and kidneys
Type III Reaction
Immune Complex Reaction
Excess antigens cause immune complexes to form in the blood.
Circulating complexes lodge in small blood vessels.
Usual sites: kidneys, skin, joints, small blood vessels
Examples of Immune Complex Reactions
Rheumatoid arthritis
Systemic Lupus Erythromatosis
Serum Sickness
Treatment of Immune Complex Reactions
corticosteroids (high dose)
RA symptoms
ulnar deviation and boutinier
high ESR, CRP and RF
Type IV reaction
Delayed Hypersensitivity
Reactive cell is T-LYMPHOCYTE (T-cell)
Antibodies and complement are not involved
Local collection of lymphocytes and macrophages cause edema, induration, ischemia, tissue damage at site.
Example of Delayed Hypersensitivity
Poison Ivy
Tissue Transplant Rejection
Autoimmunity
Process where a person develops inappropriate immune response.
Antibodies/lymphocytes directed against healthy normal cells and tissues (autoantibodies)
Immune system fails to recognize certain body cells/tissues as self, and triggers immune reactions
Sjogren’s Syndrome
Often appears with other autoimmune disorders
Dry eyes, Dry mucous membranes, vaginal dryness
Insufficient tears causing inflammation/ulceration of cornea
No cure; intensity and progression can be slowed
Goodpasture’s sydrome
Autoantibodies made agains glomerular basement membrane and neutrophils.
Affects lungs and kidneys
SOB, hemoptysis, decreased urine output, weight gain, edema, hypertension, tachycardia
Treatment high dose corticosteroids
Normal Eosinophil count
1%
Normal IgE
less than 39 IU/ml
