A 40-year-old woman who experiences severe seasonal allergies has ...

[ahriuashd]

A 40-year-old woman who experiences severe seasonal allergies has been referred by her family physician to an allergist for weekly allergy injections.
 
  The woman is confused as to why repeated exposure to substances that set off her allergies would ultimately benefit her. Which of the following phenomena best captures the rationale for allergy desensitization therapy?
  A)
  Repeated exposure to offending allergens binds the basophils and mast cells that mediate the allergic response.
  B)
  Allergens in large, regular quantities overwhelm the IgE antibodies that mediate the allergic response.
  C)
  Repeated exposure stimulates adrenal production of epinephrine, mitigating the allergic response.
  D)
  Injections of allergens simulate production of IgG, combining with the antigens to prevent activation of IgE antibodies.

Question 2

A 48-year-old man who has been HIV positive for 6 years has just learned that he has been diagnosed with Kaposi sarcoma (KS).
 
  Which of the following facts most accurately conveys an aspect of his diagnosis?
  A)
  An opportunistic Epstein-Barr virus underlies the man's KS.
  B)
  He is likely to have lesions on his skin, mouth, or GI tract.
  C)
  Intense pain was probably his first manifestation of KS.
  D)
  Heterosexual contact most likely underlies his HIV and subsequent KS.

[ghepp]

Answer to Question 1

Ans:
D

Feedback:

Repeated exposure to allergens causes an increase in IgG, which binds with antigens before they can stimulate IgE. It does not bind mast cells or basophils, nor does it overwhelm the IgE antibodies to stimulate epinephrine production.

Answer to Question 2

Ans:
B

Feedback:

The lesions of KS can be found on the skin and in the oral cavity, gastrointestinal tract, and the lungs. More than 50 of people with skin lesions also have gastrointestinal lesions. It is linked with a herpes virus and can often be painless, especially in early stages. Men who have sex with men are at a higher risk of developing KS.

[ahriuashd]

TYSM

[aliotak]

Excellent