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Doctor insights on: Positive Tb Test Look Like

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What does a positive TB test look like?

What does a positive TB test look like?

Skin test: If you had a PPD skin test and you have no risk factors, a positive test is when after 48 to 72 hoursyou have swelling in the site and redness that measures more than 15 mm, it is considered a positive tb. Test.

Dr. Scott Lindquist
609 Doctors shared insights

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What does a positive TB test look like? How is this treated?

What does a positive TB test look like? How is this treated?

What is important: Is what it feels like - not how it looks. Induration is palpated & measured. Treatment (such as INH) is determined once it is established where this is latent or active TB and the type.

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What do a positive and negative TB test look like?

What do a positive and negative TB test look like?

TB Tests: I bet you could google image that question. A positive reaction is read after 48 hours from the test. It would be a raised redness greater than 5 mm in circumference.

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What does a + TB test look like?

What does a + TB test look like?

Positive PPD test: A positive TB test should look like hard, raised bump with size >5to15 mm depending of the risk category you are in. It should be read in between 48 to72 hours. It is the hardness and not redness which is read. Thanks.

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What does a negative TB test look like?

Doc: Either your blood test igra is negative or your skin testing does not show any "bump". This should always be checked by a professional since even health care workers report false results. Best to check with a doc and not pa or np or nurse.

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What should my skin look like after taking a TB test?

What should my skin look like after taking a TB test?

See below: A positive PPD is determined by the presence of swelling (induration) around the injection site. Little or no swelling indicates a negative test. Reddness is not used to determine a neg or pos test.

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What does a positive TB test mean?

Chest X ray: It is possible to have active TB with very little symptoms especially early on. However, it is more than likely that you carry the germ for TB in a dormant form, this is called latent tb. No symptoms are expected with latent tb.

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How do I know if I have a positive TB test?

If there is a bump: When TB infects the body the infection gets walled off by antibodies. The medical person injects a manufactured antibody under your skin that reacts to the TB antibody. If a bump appears at the injection site after 48 hours it means you have the antibody to TB already in your body and therefore have TB infection. It does not mean that you have active disease or are contagious.

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How quickly will you know if you have a positive TB test?

How quickly will you know if you have a positive TB test?

48-72 hours: Tb test is meant to be interpreted in 48-72 hours after being administered on the forearm. Make sure that the induration (not redness) is measured in that time frame & results documented by a health care provider. Further testing may be determined based on your results from the TB test.

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How would I be able to tell if I have a positive TB test?

Size of induration: After the TB test, the skin at the site can develop swelling (induration). The size of this swelling (measured in millimeters by a health care provider within 48-72 hours) determines whether you have a positive result or not. It is important to not measure the area of redness but the actual size of the swelling around the test site. The cut off value for positive test is based on yr risk factors.

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Does the TB test commonly appear positive on the first day?

Yes: The TB test can become positive within the first day in someone that has been exposed to TB in the recent past.

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Could you tell me what happens if I have a positive TB test?

Latent vs active TB: If you have a + PPD then you will be screened to determine if you have TB infection or TB disease. The physician will obtain a medical history, physical examination, chest x-ray, & any other pertinent lab tests.

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How difficult must an induration be to be considered positive TB test?

PPD: It is not about hardness of the induration it is about the size of the area of induration. It is harder than surrounding skin.

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What do positive TB test results mean? How should I interpret the positive result of a TB test?

Infection with Tb: When someone is infected with tuberculosis (TB) germs, the body develops a protective response against them. The TB skin test is a test of the body's response to tb, not the germs themselves. One can have an active infection where they are coughing out TB germs and are a risk to spread tb. Or the body may have had the infection long ago and controlled it so there is no risk now of spread.

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If I tested negative from a TB test and had been around someone who tested positive am I at risk of contracting tb?

TB risk: Yes, the PPD test is not 100%. You might want to get it repeated a month later to see if it is booster positive. Of course it is also possible that you didn't catch it. Many doctors are around people with TB a lot and never catch it.

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Can weed cause a false positive TB test?

No: Have not heard about that, no relationship., .

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Will TB test be positive if one had primary complex?

Yes, I think so.: It may not be an absolute certainty, but I would advise the physician of the fact that there was a primary complex diagnosed and treated (assuming it was) either before the TB test or at the time of results if they are positive. I have never had positive results, but I was told that I had a primary complex - I always tell them the history just to be informationally complete. Best!

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Tb test site bled right after injection. Can this give a false positive? Obviously, it was not intradermal. Don't answer if you don't know how to.

Check with your doc: The test was not appropriately administered. You want to ask your doc for a new one. Or get the igra blood test which is better anyway. The skin test is almost in the museum of history of medicine.

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I had bcg. What do I do in us when TB test is positive?

I had bcg. What do I do in us when TB test is positive?

BCG: Within 3 yrs after receiving BCG most individuals do not have false positive skin tests for tb. If one has a positive PPD skin test, the overwhelming probability is that they have inactive tuberculosis.

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Why would someone born in the Netherlands get a false positive on a PPD TB test?

Why would someone born in the Netherlands get a false positive on a PPD TB test?

Usually unknown: The reasons for false positive PPD are unknown. There is speculation that it could sometimes result from past infections with various TB-like bacteria. Such infections aren't very common, but they are equally frequent in the Netherlands as anywhere else. As long as the tested person is outwardly healthy and definitely does not have tuberculosis, this is nothing to worry about.

Dr. Klaus d Lessnau
1,207 Doctors shared insights

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