Hypersensitivity (Allergy) and Autoimmunity Flashcards
(46 cards)
1
Q
Allergy
A
An inappropriate, often harmful response of the immune system to normally harmless substances
Hypersensitive reaction to an allergen initiated by immunologic mechanisms that is usually mediated by IgE antibodies
2
Q
Allergen
A
the substance that causes the allergic response
3
Q
Angioedema
A
Painless swelling under the skin
4
Q
Antibody
A
protein substance developed by the body in response to and interacting with a specific antigen
5
Q
Anaphylaxis
A
all blood vessels and bronchiolar smooth muscle cause widespread blood vessel dilation, decreased cardiac output and bronchconstriction
6
Q
erythema
A
diffuse redness of the skin
7
Q
histamine
A
substance in the body that causes increased gastric secretion, dilation of capillaries, and constriction of the bronchial smooth muscle
- cause of anaphylaxis
8
Q
hypersensitivity
A
abnormal heightened reaction to a stimulus of any kind
9
Q
immunoglobulins
A
a family of closely related proteins capable of acting as antibodies
10
Q
leukotrienes
A
a group of chemical mediators that initiate the inflammatory response
11
Q
urticaria
A
hives
12
Q
Allergic reaction:
A
- Manifestation of tissue injury resulting from interaction between an antigen and an antibody
- Body encounters allergens that are types of *antigens
- Body’s defenses recognize antigens as foreign
- Series of events occurs in an attempt to render the invaders harmless, destroy them, and remove them from the body
13
Q
Immunoglobulins and Allergic Response
A
- Antibodies (IgE, IgD, IgG, IgM, and IgA) formed by lymphocytes and plasma cells
- IgE antibodies are involved in allergic disorders
- IgE molecules bind to an allergen and trigger mast cells or basophils
- These cells then release chemical mediators such as histamine, serotonin, kinins, SRS-A, and neutrophil factor
- These chemical substances cause the reactions seen in allergic response
14
Q
Role of B Cells and T Cells in Allergic Response
A
B cells; also known as B lymphocyte
- Programmed to produce one specific antibody
- Stimulates production of plasma cells; antibody production
- Results in outpouring of antibodies
T cells; also known as T lymphocyte
- Assist B cells
- Secrete substances that destroy target cells and stimulate macrophages
- Digest antigens and remove debris
15
Q
Allergic Reaction
A
Allergen triggers the B cell to make IgE antibody, which attaches to the mast cell. When that allergen reappears, it binds to the IgE and triggers the mast cell to release its chemicals.
- Skin contact:
— poison plants
— Animal scratches
— Pollen
— Latex - Injection: bee sting
- Ingestion: medication/nut and shellfish
- Inhalation:
— Pollen
— Dust
— Mold and mildew
— Animal dander
16
Q
Hypersensitivities/Allergies
A
- Increased/excessive response to presence of antigen exposure
- Degree of reaction ranges from:
— Uncomfortable (itchy, watery eyes; sneezing)
— Life threatening (allergy asthma, anaphylaxis, bronchoconstriction, circulatory collapse
17
Q
Hypersensitivity
A
- Abnormal heightened reaction to a stimulus of any kind
- Types of hypersensitivity reactions:
— *Anaphylactic: type I; most severe
— Cytotoxic: type II
— *Immune complex: type III
— Delayed type: type IV
18
Q
Assessment of Patients With Allergic Disorders
A
- History and manifestations; comprehensive allergy history
- Diagnostic tests
— *CBC: eosinophil count
— Total serum IgE
— Skin tests: prick, scratch, and intradermal
— Allergy testing – Skin testing shows immediate hypersensitivity
19
Q
Type I: Rapid
Hypersensitivity Reactions
A
- Also called atopic allergy Most common type
- Some reactions occur only in areas of antigen exposure
- Caused by increased production of *immunoglobulin E (IgE) antibody class
- ** First time exposure body makes antigen 2nd exposure causes response
20
Q
Type I: Rapid Hypersensitivity Reactions
Allergens contracted by:
A
- Inhalation (pollens, spores, animal dander, dust, grass, ragweed)
- Ingestion (foods, food additives, drugs)
- Injection (bee venom, drugs, biologic substances)
- Contraction (latex, pollens, foods, environmental proteins)
- Eg. *Extrinsic Asthma, Allergic rhinitis, systemic anaphylaxis, reactions to bee stings.
21
Q
Type I: Anaphylactic Reaction
A
- An anaphylactic reaction is characterized by vasodilation, increased capillary, permeability, smooth muscle contraction, and eosinophilia.
- Systemic reactions may involve laryngeal stridor, angioedema, hypotension, and bronchial, G.I., or uterine spasm
- Local reactions are characterized by hives
- Examples of type I reactions include
— extrinsic asthma
— allergic rhinitis (seasonal allergies)
— Systemic anaphylaxis
— Reactions to insect stings
22
Q
Anaphylaxis
A
- Mild, moderate, and severe systemic reactions
- Symptoms are sudden in onset and progress in severity over minutes to hours
— Flushing
— Urticaria
— Angioedema
— Hypotention
— Bronchoconstriction - Common Causes; Refer to Chart 37-2 pg 1065
— Antibiotics most common; penicillin (most common cause) - Mild: something bad is going to happen/ apprehension (i feel like im going to die/ sense of doom),
- Moderate:
- Severe:
23
Q
Type 1: Rapid Hypersensitivity Reactions
A
Anaphylaxis (medical emergency)
- Life Threatening
- Rapid Onset
- Effects many systems
- Not Common
- Death due to delay of epinephrine
- S/S
— Blood vessel dilation
— Increased Cap Permeability
— Smooth Muscle Contraction
— Eosinophilia
— Laryngeal Stridor
— Angioedema
— Hypotension
— Bronchial, GI or uterine spasm
— Hives
24
Q
Angioedema
A
25
Patient-Centered Collaborative Care Assessment
- Feelings of uneasiness, apprehension, doom
- Generalized itching, urticaria
- Erythema, angioedema
- Wheals or hives
- Congestion, rhinorrhea, dyspnea, respiratory distress
26
Patient-Centered Collaborative Care Emergency Care
Interventions
- Assess respiratory function
- Establish or stabilize airway
- Stay with patient
- Epinephrine
- Antihistamines
- Oxygen
- Beta-adrenergic agonist
- Corticosteroids, oral steroids
27
Patient-Centered Collaborative Care
- Call Rapid Response team.
- Patient may lose consciousness
- Dysrhythmias, shock and Cardiac Arrest can occur within minutes due to loss of intravascular volume
28
Prevention and Management of Anaphylaxis
- Screen and prevent
- Treat respiratory problems, oxygen, intubation, and cardiopulmonary resuscitation as needed
- Epinephrine 1:1000 subcutaneously
- Auto injection system: EpiPen
- May follow with IV epinephrine
- IV fluids (to avoid shock)
29
Medications to Treat Allergic Reactions
- Oxygen, if respiratory assistance is needed
- Epinephrine used for anaphylactic reactions
- Anti-histamines- blocks histamine from binding to receptor
- *Beware patients with High Blood Pressure (may be adverse reactions)
- Corticosteroids- decrease inflammation and excess immunity
- Decongestants- vasoconstriction of inflamed tissue
30
Latex Allergy
- Type I 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 especially susceptible
- Allergic reaction to natural rubber proteins Implicated in rhinitis, conjunctivitis, contact dermatitis, urticaria, asthma, anaphylaxis
- Prevalence has been decreasing due to the use of nonlatex gloves
- 8% to 17% of healthcare workers affected Products containing Latex Table 37-5
- Different types of reactions, refer to Table 37-6
- Foley catheter
-
31
Type II: Cytotoxic Reaction
- Type II: a cytotoxic reaction, which involves binding either the IgG or IgM antibody to a cell bound antigen, may lead to eventual cell and tissue damage. The reaction is the result of mistaken identity when the system identifies a normal constituent of the body as foreign and activates the complement cascade.
- Examples of type II reactions are:
— Myasthenia gravis
— Good pasture syndrome
— Pernicious anemia
— Hemolytic disease of the newborn
— Transfusion reaction
— Thrombocytopenia
32
Type II: Cytotoxic Reactions
- Body makes special autoantibodies directed against self cells that have some form of foreign protein attached to them
- Clinical examples:
— Myasthenia Gravis – antibodies against normal nerve ending receptors
— Goodpasture’s syndrome – antibodies against lung and renal tissue
— Hemolytic anemias
— Immune thrombocytopenic purpura
— Hemolytic transfusion reactions
— Drug-induced hemolytic anemia
- Distruction of red blood cells
33
Goodpasture’s Syndrome
- Autoantibodies made against glomerular basement membrane and neutrophils
- Lungs and kidneys
- Shortness of breath, hemoptysis, decreased urine output, weight gain, edema, hypertension, tachycardia
- Treatment: – High-dose corticosteroids
- affects lung and kidneys
- treatment: suppress immune system
34
*Type III: Immune Complex Reaction
Type III:
- an immune complex reaction is marked by acute inflammation, resulting from formation and deposition of immune complexes.
- The joints and kidneys are particularly susceptible to this kind of reaction, which is associated with systemic lupus erythematosus, serum sickness, nephritis, rheumatoid arthritis.
- some signs and symptoms include urticaria, joint pain, fever, rash, and adenopathy (swollen glands)
- connective tissue diseases
35
Type III: Immune Complex Reactions
- Excess antigens cause immune complexes to form in blood
- Circulating complexes lodge in small blood vessels triggering inflammation and tissue or vessel damage
- Usual sites: Kidneys, skin, joints
- Also known as Connective Tissue Disorders
— Rheumatoid Arthritis
— Systemic Lupus erythematosus
— Serum sickness
36
Type IV: Delayed or Cellular Reaction
Type IV:
- a delayed, or cellular, reaction occurs 1 - 3 days after exposure to an antigen.
- The reaction, which result in tissue damage, involves activity by lymphokines, macrophages, and lysozymes.
- Erythema and itching are common; a few examples include:
— Contact dermatitis
— Graft vs. host disease
— Hashimoto’s thyroiditis
— Sarcoidosis
- Other examples:
— Positive purified protein derivative – *PPD for TB
— Contact dermatitis -
— Poison ivy skin rashes
— Local response to insect stings
— Tissue transplant rejection
— Sarcoidosis
https://www.youtube.com/watch?v=qleqYBPaAyc
- reaction may happen hours later
- treatment: remove pt from source, Benadryl, steroids
37
Health Promotion and Maintenance
- Prevention is best
— Medical alert bracelet
— Notify health care personnel about specific allergies
- Carry anaphylaxis kit or epinephrine injector
- Medical records should prominently display list of specific allergens
- Precautionary measures if drug or agent must be used despite history of allergic reaction
38
Self-Administration of Epinephrine
39
When could a “rebound” anaphylactic reaction occur after
an initial attack even when epinephrine has been given?
- A. 1 hour
- B. 2 hours
- C. 3 hours
- D. 4 hours
D
40
The emergency Room nurse cares for the client having an anaphylactic reaction as a result of a bee sting. The client exhibits signs of bronchial edema, hypotension, rapid pulse and pruritus at the sting site. Which is the priority action for the nurse to perform?
- a. Decrease Fluids
- b. Maintain a patent Airway
- c. Obtain an allergy history
- d. Perform allergy testing.
B
41
The client was stung by a bee less than 15 minutes ago and now presents with a Type 1 hypersensitivity Reaction. Which should the nurse do when caring for this client.
- a. Obtain immunoglobulin levels
- b. Apply a topical steroid to the site as ordered
- c. Administer antibiotics to prevent systemic infection
- d. Maintain the airway and monitor vital signs.
D
42
The emergency Room nurse cares for the client having an anaphylactic reaction as a result of a bee sting. The client exhibits signs of bronchial edema, hypotension, rapid pulse and pruritus at the sting site. Which is the priority action for the nurse to perform?
- a. Decrease Fluids
- b. Maintain a patent Airway
- c. Obtain an allergy history
- d. Perform allergy testing.
B
43
The client was stung by a bee less than 15 minutes ago and now presents with a Type 1 hypersensitivity Reaction. Which should the nurse do when caring for this client.
- a. Obtain immunoglobulin levels
- b. Apply a topical steroid to the site as ordered
- c. Administer antibiotics to present systemic infection
- d. Maintain the airway and monitor vital signs.
D
44
If a client has an anaphylactic reaction to an antibiotic it is most important for the nurse to take which action after notifying the health care provider.
- a. Administer artificial respirations
- b. Suction the airway
- c. Start an intravenous infusion
- d. Give epinephrine subcutaneously
D
45
Antigen
foreign protein or allergen
46
* Epinephrine:
Teaching
- teach how to use it:
— inject into thigh
— hold for 10 secs
— sub/ IM
— 0.3 - 0.5 ml q5-15 min as needed
-
- carry 2 pens
- how to store it
— keep in dark place
- it expires; get new ones
