Mechanism of Tetanus vaccine reaction! - USMLE Forums
USMLE Forums Logo
USMLE Forums         Your Reliable USMLE Online Community     Members     Posts
Home
USMLE Articles
USMLE News
USMLE Polls
USMLE Books
USMLE Apps
Go Back   USMLE Forums > USMLE Step 1 Forum

USMLE Step 1 Forum USMLE Step 1 Discussion Forum: Let's talk about anything related to USMLE Step 1 exam


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 12-20-2011
USMLE Forums Veteran
 
Steps History: Not yet
Posts: 281
Threads: 74
Thanked 131 Times in 68 Posts
Reputation: 141
Immunology Mechanism of Tetanus vaccine reaction!

A 18 yr old healthy boy receives tetanus vaccine. Develops a ulcer at the site on injection within few days. What's the mechanism?

A. Fixation of complement by preformed circulating antibodies
B. Antigen capture by Langerhans cells
C. Synthesis of IgM antibodies
D. Local release of histamine
E. Accumulation of Monouclear cells

Post answers with reasoning
Reply With Quote Quick reply to this message
The above post was thanked by:



  #2  
Old 12-20-2011
USMLE Forums Scout
 
Steps History: Not yet
Posts: 71
Threads: 18
Thanked 14 Times in 14 Posts
Reputation: 24
Default

I think the answer is C. coz this is Arthus reaction...in dis Tetanus antigen is injected which in turn induces antibody synthesis and thus leads to type 3 hypersensitivity reaction.
Reply With Quote Quick reply to this message
  #3  
Old 12-20-2011
USMLE Forums Veteran
 
Steps History: Not yet
Posts: 281
Threads: 74
Thanked 131 Times in 68 Posts
Reputation: 141
Default

I will post the complete question

A healthy 19-year-old man receives a tetanus
immunization booster prior to induction into the
US Marines. Six hours later, he has pain and
massive swelling at the site of injection. The
following day, the skin breaks down, forming an
ulcer at the site. Which of the following events
plays a critical role in this reaction?


(A) Accumulation of mononuclear cells at
the site of antigen injection
(B) Antigen capture by Langerhans cells in
the epidermis
(C) Local fixation of complement by
preformed circulating antibodies
(D) Local release of histamine
(E) Predominant synthesis of IgM
antibodies
Reply With Quote Quick reply to this message
The above post was thanked by:
dr.muhamad (12-20-2011)
 
  #4  
Old 12-20-2011
dr.muhamad's Avatar
USMLE Forums Guru
 
Steps History: 1 + CS
Posts: 300
Threads: 22
Thanked 97 Times in 62 Posts
Reputation: 107
Default

i go with A it is granulation ??
Reply With Quote Quick reply to this message
  #5  
Old 12-20-2011
USMLE Forums Veteran
 
Steps History: Not yet
Posts: 281
Threads: 74
Thanked 131 Times in 68 Posts
Reputation: 141
Default

ans is Local fixation of complement by
preformed circulating antibodies
Reply With Quote Quick reply to this message
  #6  
Old 12-20-2011
dr.muhamad's Avatar
USMLE Forums Guru
 
Steps History: 1 + CS
Posts: 300
Threads: 22
Thanked 97 Times in 62 Posts
Reputation: 107
Default

Quote:
Originally Posted by indigo View Post
ans is Local fixation of complement by
preformed circulating antibodies
coz it is 6 hr right?
Reply With Quote Quick reply to this message
  #7  
Old 12-20-2011
USMLE Forums Veteran
 
Steps History: Not yet
Posts: 281
Threads: 74
Thanked 131 Times in 68 Posts
Reputation: 141
Default

I think this is the way it happens
First time when u give the dose,IgM,followed by IgG forms.

At a later stage when you give booster I guess IgG causes complement activation at the site.

Correct me if I am wrong.
Reply With Quote Quick reply to this message
The above post was thanked by:
dr.muhamad (12-20-2011)
  #8  
Old 12-20-2011
USMLE Forums Veteran
 
Steps History: Not yet
Posts: 281
Threads: 74
Thanked 131 Times in 68 Posts
Reputation: 141
Default

After initial immunization, a booster injection is essentially a reexposure to
the immunizing antigen (tetanus toxoid, in this case). The reaction described is sometimes called the
Arthus reaction, a localized form of type III hypersensitivity, induced by fixation of complement by
preformed circulating antibodies. In severe cases, the degree of complement fixation can be so
substantial that it induces local tissue necrosis.
This reaction is mediated predominantly by vascular changes induced by the complement reaction rather
than by accumulation of mononuclear cells (choice A).
This reaction consumes preformed (usually IgG) antibodies and does not require antigen capture by
Langerhans cells in the epidermis (choice B).
This reaction does not involve the IgE/histamine pathway (choice D).
This reaction utilizes preformed (usually IgG) antibodies rather than requiring IgM synthesis (choice E).
Reply With Quote Quick reply to this message
The above post was thanked by:
drortho (01-18-2012), Learner (12-20-2011), sumedha (12-20-2011)



Reply

Tags
Immunology-, Step-1-Questions

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the USMLE Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Medical School
Choose "---" if you don't want to tell. AMG for US & Canadian medical schools. IMG for all other medical schools.
USMLE Steps History
What steps finished! Example: 1+CK+CS+3 = Passed Step 1, Step 2 CK, Step 2 CS, and Step 3.

Choose "---" if you don't want to tell.

Favorite USMLE Books
What USMLE books you really think are useful. Leave blank if you don't want to tell.
Location
Where you live. Leave blank if you don't want to tell.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
When to give Tetanus immunoglobulin prophylaxis? docoftheworld USMLE Step 2 CK Forum 21 04-29-2013 04:25 AM
reaction to tetanus immunization Seetal USMLE Step 1 Forum 4 10-06-2011 09:26 AM
Treatment of acute tetanus infection Seetal USMLE Step 2 CK Forum 4 06-14-2011 04:33 AM
Immunological Mechanism of Hemolytic Transfusion Reaction! Dr_Laura USMLE Step 1 Forum 8 05-10-2011 11:50 AM
Reaction to Influenza Vaccine! dezirablize USMLE Step 2 CK Forum 3 10-14-2010 02:04 PM

RSS Feed
Find Us on Facebook
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

USMLE® & other trade marks belong to their respective owners, read full disclaimer
USMLE Forums created under Creative Commons 3.0 License. (2009-2014)