Immune Dysfunction

Question 1

What aspect of our immune system is rapid, non-specific, and does not provide long-lasting protection?

Answer 1

Innate Immunity

has no memory, but the response is always identical

S3

Question 2

What are the 4 cellular components of the innate immunity system?

Answer 2

• Neutrophils
• Macrophages
• Monocytes
• NK cells (Natural Killer Cells)

S4

Question 3

What cell (of the innate immunity response) responds the fastest to infection?

Answer 3

Neutrophils

S4

Question 4

What cell (of the innate immunity response) provides a slower but more prolonged response to infection?

Answer 4

Macrophages

S4

Question 5

What are the characteristics and actions of neutrophils?

Answer 5

• Migrate rapidly to bacterial infections
• Release cytokines to phagocytize
• ½ life is 6 hours
• Sensitive to acidic infection environments
• Become purulent exudate

S6

Question 6

What type of immune cell is the largest blood cell and what is their role?

Answer 6

• Monocytes (largest blood cell)
• Circulates to specific tissue areas to differentiate into macrophages

not mentioned in lecture - but the chart also shows them turning into dendritic cells - and we know how tricky they like to be

S7

Question 7

What are the pertinent characteristics of monocytes/macrophages?

Answer 7

• Mobilize just after neutrophils
• Phagocytic destruction via NO & cytokines
• Persist at site in chronic infections (fight infection long term)

S7

Question 8

What cells play a major role in allergies, asthma, and eczema?

Answer 8

Basophils and Mast cells

S8

Question 9

What characteristics does Adaptive Immunity possess?

Answer 9

• Present only in Vertebrates
• Delayed onset of action
• Capable of memory and specific antigen response

Vaccinations are also a form of adaptive memory

S10

Question 10

What are the cellular components of the adaptive immunity system?

Answer 10

Helper T-cells
Cytotoxic T-cells

S11

Question 11

Where do T-cells originate? Where do they mature?

Answer 11

T-cells originate in the bone marrow and mature in the Thymus.

S11

Question 12

What is hypersensitivity?

Answer 12

Foreign antigen reaction which causes altered T-cell and antibody response

Response varies from uncomfortable rash to fatal anaphylaxis

S14

Question 13

What occurs during a Type I Allergic Response?

Answer 13

• 1st exposure: T-Cells stimulate B cells to produce IgE immediately
• 2ⁿᵈ exposure: Antigen releases Ca⁺⁺ → histamine, inflammatory mediators, heparin are released.

(Histamine triggers: bronchostriction, Vascular permeability, vasodilation, gastric acid)

S15

Question 14

What are common drugs used to prevent the histamine effects of Type I allergic responses?

Answer 14

• Antihistamines
• Cromolyn Na⁺
• Bronchodilators
• COX Inhibitors
• Diagnostic allergen tests
  
  • small doses of allergen to desensitize

S16

Question 15

What is another name for Type II Allergic Responses?
What mediates these types of responses?
What is the reaction severity and time?

Answer 15

• Cytotoxic Hypersensitivity
• Mediated by IgG, IgM, and Complement system → activate B-cells → produce antibodies.
• Severity will vary - reaction time in minutes or hours

mediated by GMC

S17

Question 16

What are examples of Type II Allergic Responses?

Answer 16

• Hemolytic Anemia
• Myasthenia Gravis
• Transfusion Reactions

S17

Question 17

What is the treatment for Type II Allergic Responses?

Answer 17

• Anti-inflammatories
• Immunosuppressants
• IVIG up and coming

S17

Question 18

What is another name for Type III Allergic Response?

Answer 18

Immune Complex Hypersensitivity

S18

Question 19

What occurs with Type III Allergic Response?

Answer 19

Failure of immune system to eliminate antibody-antigen complex.
- Build up in the joints, kidneys, skin and eyes

S18

Question 20

What are examples of Type III Allergic Responses?

Answer 20

Systemic Lupus Erythematosus and Rheumatoid arthritis

S18

Question 21

Treatment for type III allergic response?

Answer 21

• Anti-inflammatories
• might need immunisuppressives

S18

Question 22

What is a Type IV Allergic Response?

Answer 22

T-lymphocyte and monocyte/macrophage mediated response that does not involve antibodies.

S19

Question 23

What are examples of Type IV Allergic Responses?

Answer 23

• Contact Dermatitis
• Tuberculosis
• Stevens-Johnson Syndrome

S19

Question 24

Treatment for type IV allergic reaction?

Answer 24

• anti-inflammatories
• immunosuppressives

S19

Question 25

What is Biphasic anaphylaxis?

Answer 25

- Occurs following an asymptomatic period **without second exposure** - Secondary anaphylactic episode occurring 8 - 72 hours later. *occurs is 4-5% of the pts that experience anaphylaxis* | S23

Question 26

What are risk factors for a secondary anaphylactic episode?

Answer 26

- Severe initial response - Initial response required multiple epi doses | S23

Question 27

What is the epinephrine dose for adult anaphylaxis?

Answer 27

10 mcg - 1000mcg IVP q 1-2 min | S26

Question 28

What is the crystalloid dosage for anaphylaxis?

Answer 28

NS: 10 - 25 mL/kg over 20 min repeat PRN | S26

Question 29

What is the colloid dosage for anaphylaxis?

Answer 29

10 mL/kg over 20 min repeat PRN | S26

Question 30

Why is epinephrine the drug of choice for anaphylaxis?

Answer 30

- ↓ degranulation of mast cells & basophils → reduced vasodilation - α1 = Increased blood pressure - β1 = positive Inotropy & chronotropy - β2 = Bronchodilation | S27

Question 31

What drug classes are secondary treatments for anaphylaxis?

Answer 31

- Bronchodilators - Antihistamines - Corticosteroids | S28