What is considered a positive TB test, 10mm or 15mm?

Nurses General Nursing

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In school I was taught 15mm but on CDC its giving two different answers which can i go by for standard?

1)I did not say anything about chicken pox

2)what does being of Indian descent have to do with him not having had chicken pox?

1) I meant smallpox

2) Some countries TB are more prevalent just thought I'd mention

1) I meant smallpox

2) Some countries TB are more prevalent just thought I'd mention

Ok, well, my comment about smallpox was actually facetious, considering that:

The last known natural case was in Somalia in 1977. Since then, the only known cases were caused by a laboratory accident in 1978 in Birmingham, England, which killed one person and caused a limited outbreak. Smallpox was officially declared eradicated in 1979.

WHO | Frequently asked questions and answers on smallpox

Specializes in Psych, Corrections, Med-Surg, Ambulatory.

The WHO, CDC have websites about TB. Health Canada has very good information also. The WHO has an interactive BCG website, telling you which countries administer BCG to their citizens. The CDC has an algorithm for how to determine a positive skin test based on mm induration and risk factors.

If the patient is from India he was more than likely vaccinated with BCG which would give a false positive. He really needs a quantiferon or T-spot to clarify. If that test is positive, then he needs a chest x-ray to rule out active disease. If the QFG is positive, but the CXR negative, then he has latent tb infection and needs to be counseled so he can make an informed decision whether to start chemoprophylaxis. If the CXR is positive, then he has active TB and definitely needs to be treated. Clear as mud?

The WHO, CDC have websites about TB. Health Canada has very good information also. The WHO has an interactive BCG website, telling you which countries administer BCG to their citizens. The CDC has an algorithm for how to determine a positive skin test based on mm induration and risk factors.

If the patient is from India he was more than likely vaccinated with BCG which would give a false positive. He really needs a quantiferon or T-spot to clarify. If that test is positive, then he needs a chest x-ray to rule out active disease. If the QFG is positive, but the CXR negative, then he has latent tb infection and needs to be counseled so he can make an informed decision whether to start chemoprophylaxis. If the CXR is positive, then he has active TB and definitely needs to be treated. Clear as mud?

YES! THANKS TriciaJ

Specializes in Urgent Care, Oncology.
I'm going to go out on a limb and guess that the patient has not recently had smallpox...;)

But good points made about false positives as well as the BCG.

LOL I meant to type chickenpox.

Specializes in Urgent Care, Oncology.

So I just saw on IFLScience that some kid in Idaho had the Bubonic plague. So never say never! I know it still is possible in certain parts of the world/country, but that was not something I was expecting to see it.

Specializes in Medsurg/ICU, Mental Health, Home Health.
what does being of Indian descent have to do with him not having had chicken pox?

A lot of people in India are vegetarians, therefore they can't contract chicken pox.

Duh.

I'll see myself out.

A lot of people in India are vegetarians, therefore they can't contract chicken pox.

Duh.

I'll see myself out.

Gigglesnorted so hard I almost gave myself a nosebleed.

Thanks for that lmao

Specializes in Psych, Corrections, Med-Surg, Ambulatory.
A lot of people in India are vegetarians, therefore they can't contract chicken pox.

Duh.

I'll see myself out.

Exactly. That's why Hindus don't get cowpox and Muslims don't get swine flu.

Specializes in Public Health, TB.

Beware the Skittle pox !

1) I meant smallpox

2) Some countries TB are more prevalent just thought I'd mention

Asians have a high prevalence of TB. My ex is filipino and she wanted to be a CNA so she had to get tested for TB. She tested positive via the shot, then had X-ray done and was tested positive for that to see how big it was in her lungs, but that didn't mean she couldn't be a CNA. She had no S&S. I can't remember the size, but she said she knew she had it because asians get it all the time, butI can't remember the size, but she was waived I think because it was too small.

Exactly. That's why Hindus don't get cowpox and Muslims don't get swine flu.

I think I read in my patho book that people with sickle cell disease are immune from getting malaria which is the only benefit for being sickle cell disease.

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