9 doctors weighed in:

If a person had BCG shot as a child, will he always test positive when skin tested for tb?

9 doctors weighed in
Dr. Theresa Willett
Pediatrics
5 doctors agree

In brief: Maybe

Often people who were immunized against tuberculosis w BCG will react to the tuberculin skin test (tst).
However, some people do not, and we do not have good data on how long to 'blame' BCG for a positive test. Given this uncertainty, the first finding of a positive tst needs to be treated like a true positive in terms of further testing, such as w x-ray.

In brief: Maybe

Often people who were immunized against tuberculosis w BCG will react to the tuberculin skin test (tst).
However, some people do not, and we do not have good data on how long to 'blame' BCG for a positive test. Given this uncertainty, the first finding of a positive tst needs to be treated like a true positive in terms of further testing, such as w x-ray.
Dr. Theresa Willett
Dr. Theresa Willett
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3 comments
Dr. Joseph Eastern
This point is moot, IMHO. We should always treat a positive PPD as a true positive, and follow it up with a chest Xray. It's never wise to assume BCG is responsible, since the patient could have active TB as well.
Dr. Jay Park
Even in asymptomatic individual, TST reaction over 15mm or positive TST with the interval from administration of BCG over 5 years raise suspicion of latent tuberculosis infection.
Dr. Joseph Eastern
Dermatology
2 doctors agree

In brief: Yes.

Most people vaccinated with BCG will always have a false-positive TB test.
To rule out active tb, they need either a chest xray or the new qftb gold test instead.

In brief: Yes.

Most people vaccinated with BCG will always have a false-positive TB test.
To rule out active tb, they need either a chest xray or the new qftb gold test instead.
Dr. Joseph Eastern
Dr. Joseph Eastern
Thank
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