Block 9 Hypersensitivity MCQ's

1.

Regarding anaphylactic (type I) and immune complex (type III) hypersensitivities, which of the following is the MOST accurate?

Discuss
- A.
  
  IgE is involved in both anaphylactic and immune complex hypersensitivibes
- B.
  
  Complement is involved in both anaphylactic and immune complex hypersensitivities
- C.
  
  Less antigen is typically needed to trigger and anaphylactic reaction than an immune complex reaction
- D.
  
  Neutrophils play more important role in anaphylactic reactions than in immune complex reactions
2.

A patient was undergoing a series of surgical procedures requiring general anesthetic. At the third procedure he suddenly became hypotensive with marked cardiac arrhythmia. In addition his breathing became difficuft due to extensive bronchocorstriction and obstructive laryngeal edema. Despite the efforts of the surgical team the patient developed severe and permanent brain damage due to hypoxernia. It was subsequently discovered that the patient had developed IgG antibodies to the anesthetic gas and this had resulted in an anaphylactoid response to the anesthetic. What type of reaction caused this condition?

Discuss
- A.
  
  Type I Hypersensitivity
- B.
  
  Type II Hypersensitivity
- C.
  
  Type III Hypersensitivity
- D.
  
  Type IV Hypersensitivity
- E.
  
  Direct activation of mast cells by the anesthetic gas
3.

Leprosy is a chronic infectious disease caused by Mycobacterium leprae. The ability of this organism to cause disease is related to it’s ability to infect, persist in, and replicate within macrophages. The lepromin skin test is used to determine what type of leprosy a person has. In this test, inactivated Mycobacterium leprae organisms are injected just beneath the skin. At the site of injection, a person with a positive test will develop an area of induration with erythema peaking around 48 hours after the injection. If this test measures a hypersensitivity reaction against the organism, what type of hypersensitivity reaction is it intended to detect?

Discuss
- A.
  
  Type I
- B.
  
  Type IV
- C.
  
  Type II
- D.
  
  Type II or III
- E.
  
  Type III
4.

The principle difference between type II and type III hypersensitivity is:

Discuss
- A.
  
  The class (isotype of antibody)
- B.
  
  Whether the antibody reacts with the antigen on the cell or reacts with antigen before it interacts with the cell
- C.
  
  The participation of complement
- D.
  
  The participation of T cells
5.

A child stung by a bee experiences respiratory distress within minutes and lapses into unconsciousness. This reaction is probably mediated by:

Discuss
- A.
  
  IgE antibody
- B.
  
  IgG antibody
- C.
  
  Sensitized T cells
- D.
  
  Complement
- E.
  
  IgM antibody
6.

A patient with severe asthma gets no relief from antihistamines. The symptoms are MOST likely to be caused by:
- A.
  
  IL-2
- B.
  
  Leukotrienes
- C.
  
  Serotonin
- D.
  
  Bradykinin
7.

Hypersensitivity to penicillin and hypersensitivity to poison oak are both:
- A.
  
  Mediated by IgE antibody
- B.
  
  Mediated by IgG and IgM antibody
- C.
  
  Intiated by haptens
- D.
  
  Initiated by Th2 cells
8.

Your patient has been treated for endocarditis with Penicillin G for the past 2 weeks. She now has fever and maculopapular erythematous rash over her chest and abdomen. A urinalysis shows significant protein in the urine. If the fever, rash and proteinuria are immunologic in origin, which one of the following is MOST likely to be involved?

Discuss
- A.
  
  IgG and complement
- B.
  
  IgE and histamine
- C.
  
  IL-2 and cytotoxic T cells
- D.
  
  Gamma interferon and macrophages
9.

A child disturbs a wasp nest, is stung repeatedly, and goes into shock within minutes, manifesting respiratory failure and vascular collapse. This is MOST likely due to;
- A.
  
  Systemic anaphylaxis
- B.
  
  Serum sickness
- C.
  
  An Arthus reaction
- D.
  
  Cytotoxic hypersensitivity
10.

A delayed hypersensitivity reaction is characterized by:

Discuss
- A.
  
  Edema without a cellular infiltrate
- B.
  
  An infiltrate composed of neutrophiis
- C.
  
  An infiltrate composed of helper T cells and macrophages
- D.
  
  An infiltrate composed of eosinophils
11.

In Henoch-Schonlein purpura, what is the reason for the purpuric rash?

Discuss
- A.
  
  Bacteria that adhere to vascular walls inducing necrosis
- B.
  
  IgM immune complexes that induce vasculitis
- C.
  
  Immune-mediated destruction of bacteria, releasing endotoxin
- D.
  
  The disease is a the result of superantigen activity by the infectious agent
- E.
  
  IgA immune complexes that induce vasculitis
12.

A 44-year-old man is given an intramuscular high dose of penicillin. About 8 days later, he develops chills, fever and a rash, If his symptoms are due to an immune reaction to the drug, what type of reaction is this considered?

Discuss
- A.
  
  Type I Hypersensitivity reaction
- B.
  
  Type II Hypersensitivity reaction
- C.
  
  Type IV Hypersensitivity reaction
- D.
  
  Anaphylactoid reaction
- E.
  
  Type III Hypersensitivity reaction