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  #1  
Old 04-27-2010
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Immunology reaction to tetanus immunization

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 atthe site of antigen injection
(B) Antigen capture by Langerhans cells inthe epidermis
(C) Local fixation of complement bypreformed circulating antibodies
(D) Local release of histamine
(E) Predominant synthesis of IgMantibodies
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  #2  
Old 04-27-2010
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Default C--Local fixation of complement by preformed circulating antibodies

Tough question!
It looks like an Arthus reaction. I m not sure but I choose C
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  #3  
Old 04-27-2010
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Default C.

Type 3 hypersensitivity, Arthus reaction.

Local antibody-mediated hypersensitivity reaction in which antibody-antigen complexes which fix complement are deposited in the walls of small vessels causing acute inflammation with an infiltration of neutrophils.
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Old 10-06-2011
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hmm... preformed antibodies?

cant the answer be B?
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Old 10-06-2011
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The answer is c type 3 arthus reaction
taken from kaplan q bbank
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