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Discussion Starter · #1 ·
A 33-year-old woman presents with worsening episodes of fever, non-productive cough, and dyspnea over 5 months. She is a nonsmoker with no past medical history. She recently immigrated from Europe and works as a clerk in a bird pet store. There are no abnormal findings on physical examination. A CXR shows fine, diffuse, nodular infiltrates in all lung fields. Which of the following is consistent with her disease?
• A. Progressive interstitial fibrosis
• B. Type III hypersensitivity reaction
• C. Type IV hypersensitivity reaction
• D. Type I hypersensitivity reaction
• E. Langerhans cell proliferation
 

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E. Langerhans cell proliferation...?? or it can be type 4 hypersensitivity reaction if we consider histoplasmosis....:eek:
hmmmm.....will go with type 4 reaction....:redcheeks;
 

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idk. whenever birds are involved we're supposed to think of Chlamydia psittaci and Histoplasma right? idk what kind of hypersensitivity reaction would be involved in either case.
 

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E. Langerhans cell proliferation ??
 

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Discussion Starter · #7 ·
The correct answer is B.
Dust from bird feathers can result in an extrinsic allergic alveolitis. This type of pulmonary alveolitis is a result of an antigen-antibody complex formation type III hypersensitivity reaction. Removing the antigen source will improve the symptoms.

Type I hypersensitivity is seen with extrinsic asthma, where an allergen attaching to IgE bound to mast cells causing mast cell degranulation. Type IV hypersensitivity occurs with cell-mediated immune responses to tuberculosis. Interstitial fibrosis and Langerhans cell histiocytosis have a progressive course (not episodic) and lead to restrictive lung disease.
 

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The correct answer is B.
Dust from bird feathers can result in an extrinsic allergic alveolitis. This type of pulmonary alveolitis is a result of an antigen-antibody complex formation type III hypersensitivity reaction. Removing the antigen source will improve the symptoms.

Type I hypersensitivity is seen with extrinsic asthma, where an allergen attaching to IgE bound to mast cells causing mast cell degranulation. Type IV hypersensitivity occurs with cell-mediated immune responses to tuberculosis. Interstitial fibrosis and Langerhans cell histiocytosis have a progressive course (not episodic) and lead to restrictive lung disease.
which Q bank u r using?...:eek:
hope i wont see this type of Q in exam.....:eek:
 

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Discussion Starter · #9 ·
which Q bank u r using?...:eek:
hope i wont see this type of Q in exam.....:eek:
lolzzz this is from the gunnertraining question bank i won from here!!:)
 

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No Keywords

Wow -sometimes these people really take these Qbanks to the next level by removing any preformed associations we may have in our heads. Birds are supposed to be a HUGE keyword for histo and c. psittaci and now we're supposed to remember birds are dusty? Don't they clean the birds in the pet store ;)?

One thing though - I'm a little confused... doesn't dust cause asthma and therefore a type I hypersensitivity? I thought Type III was more systemic like SLE. FA's table lists something called "Hypersensitivity Pneumonitis eg. Farmer's Lung" - is this an example of that? (FA2010 p.209)
 
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