Prep for USMLEPrep for USMLE Forum
   Forum    Step 1  Step 2 CK Step 2 CS Step 3  Match  IMGs Resources Search






Previous Topic | Next Topic  Primary Defense Mech 




 
Kaplan Qbank USMLE



Author8 Posts
  #1

A 45-year-old homeless man has a chronic cough, a cavitary lesion of the lung, and is sputum positive for acid-fast bacilli.

Which of the following is the principle form of defense by which the patient's body fights this infection?

A. Antibody-mediated phagocytosis
B. Cell-mediated immunity
C. IgA-mediated hypersensitivity
D. IgE-mediated hypersensitivity
E. Neutrophil ingestion of bacteria


___________________
FORUM RULES-- Those who believe in telekinesis, raise my hand. I get enough exercise just by pushing my luck --P4U World.." The pure and simple truth is rarely pure and never simple."

  #2

e?

___________________
we are all in the gutter but some of us looking at the stars

  #3

shaking headshaking head

___________________
FORUM RULES-- Those who believe in telekinesis, raise my hand. I get enough exercise just by pushing my luck --P4U World.." The pure and simple truth is rarely pure and never simple."

  #4

Its an Easy Try Again .............

___________________
FORUM RULES-- Those who believe in telekinesis, raise my hand. I get enough exercise just by pushing my luck --P4U World.." The pure and simple truth is rarely pure and never simple."

  #5

b?

___________________
we are all in the gutter but some of us looking at the stars

  #6

yoga wrote:
b?

nodnod

___________________
FORUM RULES-- Those who believe in telekinesis, raise my hand. I get enough exercise just by pushing my luck --P4U World.." The pure and simple truth is rarely pure and never simple."

  #7

The correct answer is B.

The principle host defense in mycobacterial infections (such as this patient's tuberculosis) is cell-mediated immunity, which causes formation of granulomas. Unfortunately, in tuberculosis and in many other infectious diseases characterized by granuloma formation, the organisms may persist intracellularly for years in the granulomas, only to be a source of activation of the infection up to decades later.

While antibody-mediated phagocytosis (choice A) is a major host defense against many bacteria, it is not the principle defense against Mycobacteria.

IgA-mediated hypersensitivity (choice C) is not involved in the body's defense against Mycobacteria.

IgE-mediated hypersensitivity (choice D) is not involved in the body's defense against Mycobacteria. It is important in allergic reactions.

Neutrophil ingestion of bacteria (choice E) is a major host defense against bacteria, but is not the principle defense against Mycobacteria.


___________________
FORUM RULES-- Those who believe in telekinesis, raise my hand. I get enough exercise just by pushing my luck --P4U World.." The pure and simple truth is rarely pure and never simple."

  #8

nod

___________________
“When a person really desires something, all the universe conspires to help that person to realize his dream.”







You don't have permission to post.




Login or Register to post messages in this topic





















Contact | Leaders | Disclaimer | Privacy

Copyright @ Prep for USMLE. All rights reserved.