Hypersensitivity Responses II

Question 1

What type of hypersensitivity reaction is associated with serum sickness?

Answer 1

Type III hypersensitivity reaction (p.203)

Question 2

Descrive serum sickness.

Answer 2

An immune complex condition in which antibodies to foreign proteins are produced 5 days after exposure. Immune complexes form and are deposited in membranes where they fix complement, leading to tissue damage. This is more common than the Arthus reaction (p.203)

Question 3

What type of hypersensitivity reaction is associated with the Arthus reaction?

Answer 3

Type III hypersensitivity reaction (p.203)

Question 4

What is the Arthus reaction?

Answer 4

A local, subacute antibody mediated hypersensitivity reaction where intradermal injection of antigen induces antibodies which form antigen-antibody complexes in the skin.

Question 5

What characterizes an Arthus reaction?

Answer 5

Edema, necrosis, and complement activation (p.203)

Question 6

What causes most cases of serum sickness?

Answer 6

Drugs that act as haptens (p.203)

Question 7

Describe the symptoms and time frame of a drug induced serum sickness reaction.

Answer 7

Symptoms: fever, urticaria, arthralgias, proteinuria, lymphadenopathy. This occurs 5-10 days post exposure (p.203)

Question 8

What test can be used to diagnose an Arthus reaction?

Answer 8

Immunofluorescent staining (p.203)

Question 9

Describe the antigen response to a type IV hypersensitivity reaction.

Answer 9

Delayed, T cell mediated reaction where sensitized T lymphocytes encounter antigen and then release lymphokines. Lymphokines cause macrophage activation without the involvement of antibody. This reaction is not transferrable by serum (p.203)

Question 10

Name three instances in which type IV hypersensitivity reactions occur.

Answer 10

Transplant rejections, TB skin tests, contact dermatitis (p.203)

Question 11

What test can be used to diagnose a type IV hypersensitivity reaction?

Answer 11

Patch test, PPD (p.203)

Question 12

Briefly characterize the four types of hypersensitivity reactions.

Answer 12

(acronym- ACID); Anaphylactic and atopic (type I); Cytotoxic, antibody mediated (type II); Immune complex (type III); Delayed cell mediated reaction (type IV) (p.203)

Question 13

What are the two categoric conditions associated with a type I hypersensitivity disorder?

Answer 13

Anaphylaxis (bee sting, food/drug allergies); allergic and atopic disorders (rhinitis, hay fever, eczema, hives, asthma) (p.204)

Question 14

Name nine examples of type II hypersensitivity conditions.

Answer 14

1.) Autoimmune hemolytic anemia (AIHA); 2.) Pernicious anemia; 3.) Idiopathic thrombocytopenic purpura; 4.) Erythroblastosis fetalis; 5.) Acute hemolytic transfusion reactions; 6.) Rheumatic fever; 7.) Goodpasture’s syndrome; 8.) Bullous pemphigoid; 9.) Pemphigus vulgaris (p.204)

Question 15

What tissues/ sites are prone to type II hypersensitivity reactions?

Answer 15

Tissues or sites where the antigen is found; Reaction is specific to these sites (p.204)

Question 16

Name five examples of type III hypersensitivity conditions.

Answer 16

1.) SLE; 2.) polyarteritis nodosa; 3.) poststreptococcal glomerulonephritis; 4.) serum sickness; 5.) Arthus reaction (i.e. swelling/ inflammation following tetanus vaccine) (p.204)

Question 17

Can type III hypersensitivity reactions have systemic responses?

Answer 17

Yes. Type III reactions can be associated with vasculitis and systemic manifestations (p.204)

Question 18

Name five examples of type IV hypersensitivity conditions.

Answer 18

1.) Multiple sclerosis; 2.) Guillain Barr̩ syndrome; 3.) Graft vs Host disease; 4.) PPD; 5.) Contact dermatitis (posion ivy, nickel, etc)

Question 19

What is the pathogenesis of a blood transfusion allergic reaction?

Answer 19

Type I hypersensitivity reaction against plasma proteins of transfused blood (p.204)

Question 20

What is the clinical presentation of an allergic reaction caused by a blood transfusion?

Answer 20

Urticaria, pruritus, wheezing, fever (p.204)

Question 21

How do you treat an allergic reaction caused by a blood transfusion?

Answer 21

Antihistamines (p.204)

Question 22

What is the clinical presentation of a blood transfusion anaphylactic reaction?

Answer 22

A severe reaction with dyspnea, bronchospasm, hypotension, respiratory arrest, shock (p.204)

Question 23

Why must IgA deficient individuals be identified prior to a transfusion reaction?

Answer 23

IgA deficient individuals must receive blood products that lack IgA (p.204)

Question 24

What is the pathogenesis of a blood transfusion febrile nonhemolytic transfusion reaction (FNHTR)?

Answer 24

A type II hypersensitivity reaction in which host antibodies against donor HLA antigens and leukocytes are formed (p.204)

Question 25

What is the clinical presentation of a blood transfusion febrile nonhemolytic transfusion reaction (FNHTR)?

Answer 25

Fever, headaches, chills, flushing (p.204)

Question 26

What is the pathogenesis of a blood transfusion acute hemolytic transfusion reaction (HTR)?

Answer 26

A type II hypersensitivity reaction with intravascular hemolysis (ABO blood group incompatability) or extravascular hemolysis (host antibody reaction against foreign antigen on donor RBCs) (p.204)

Question 27

What is the clinical presentation of a blood transfusion acute hemolytic transfusion reaction (HTR)?

Answer 27

Fever, hypotension, tachypnea, tachycardia, flank pain, hemoglobinuemia (intravascular), jaundice (extravascular hemolysis) (p.204)