Lung patho 1

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Lung patho 1

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jean robert
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12/26/07 - 01:01 PM

A 10 y.o. XX who participated in a screening program develop a 10 mm area of induration on her left forearm 3 days after intracutaneous injection of 0.1 ml of PPD. She appears healthy. A chest radiograph is most likely to demonstrate:

a) Marked hilar adenopathy

b) Upper lobe calcifications

c) Extensive opacification

d) Cavitary change

e) No abnormal findings

Edited by jean robert on 12/26/07 - 01:34 PM

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angel23
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12/26/07 - 01:07 PM

arlete
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12/26/07 - 01:49 PM

E

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Tiff
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12/26/07 - 01:59 PM

E - no abnormal findings

new_n_lost
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12/26/07 - 04:47 PM

Ok A child with 10 mm reaction can be considered positive even if they have had BCG vaccination as it has no affect on the TST results. Now this child can be considered having the disease and primary TB infection usually presents as an seasonal fever or flu like prodromal symptoms. However if a CXR is done on those children we might almost 60% of them having Hilar lymphadenopathy which is usually absent in REactivation or post primary TB >> Moi 2 Cents

So i will go with A

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Tiff
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12/26/07 - 07:50 PM

Hi NNL. I think I understand what you're saying. But shouldn't we assume that the child does not have any symptoms since she appears healthy.

new_n_lost
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12/26/07 - 08:03 PM

Tiff wrote:
Hi NNL. I think I understand what you're saying. But shouldn't we assume that the child does not have any symptoms since she appears healthy.

Hi there Tiff,

Even so under the assumption of her being healthy and not showing any symptoms the results of her TST test give us a clue of her TB infection status. Whether the Child goes on to develop full blown primary TB infection or recovers full from this episode is subject to discussion. But during her resistence to infection or lets say the body is fighting it, the most primary site of her fight would in the lymph nodes or the lung parenchyma. (Ghon Complex). Thus if she is having the disease and is asymptomatic there would be hilar lymphadenopathy.

This my opinion though i might wrong it but i m pretty sure of it.

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GoodGirl
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12/26/07 - 08:49 PM

Uff, aff, och..... gasping....uffff.....

shaking head

E

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Tiff
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12/27/07 - 09:32 AM

Yeah NNL - I see your point. A couple questions I ask myself is...1) What is most likely to be seen - false positve or true positive? 2)What is the cutoff point for someone without risk factors? Because the question doesn't elude to the child being around any sick contacts, I'm still left to think that it might be a false positive. Wish I knew the answer. confused

arlete
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12/27/07 - 10:38 AM

#10

False positive is what we see the most.

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angel23
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12/27/07 - 12:42 PM

#11

i think in high risk areas like in developing countries where the incidence is high for TB.... ppd of >15mm is considered to b diagnostic
otherwise insignificant
i l go with E

Tiff
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12/27/07 - 02:11 PM

#12

Found this article. Should help. It has the cutoffs for PPD tests. 15 mm is positive for a person with no risk factors.

http://findarticles.com/p/articles/mi_g2601/is_20...

angel23
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12/27/07 - 02:24 PM

#13

thanks tiff....
what do u think the answer is...is it E?

Tiff
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12/27/07 - 02:45 PM

#14

Yeah - pretty much think it's E.

jean robert
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12/27/07 - 09:55 PM

#15

angel23 wrote:
E raised eyebrow

Correct Answer: E

Most M. Tuberculosis infections are asymptomatic and subclinical. Active disease is uncommon, although a preceding illness or poor living conditions increase the risk.

Lymphadenopathy is more frequent with primary tuberculosis infections.

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