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A 39-year-old member asked:

Is the skin test as accurate as a chest x-ray for tb?

4 doctor answers14 doctors weighed in
Dr. Rakhi Dimino
Specializes in Obstetrics and Gynecology
No: The skin test is a screening test to see if you might have been exposed to or contracted tb. If the skin test is positive, a chest x-ray is done to see if you have active tb.
Created for people with ongoing healthcare needs but benefits everyone.
Dr. Alfredo Garcia
Pediatrics 57 years experience
TB test: The skin test (tuberculin, ppd) is very accurate in detecting the presence of tuberculosis. A chest x-ray will show positive findings of tuberculosis only if there is active disease. A negative chest x-ray does not rule out tuberculosis but a positive tuberculin will, despite absence of symptoms.
Created for people with ongoing healthcare needs but benefits everyone.
Dr. Geoffrey Rutledge
Internal Medicine 42 years experience
Yes and no: The skin test almost always shows if you have been exposed to TB but does not mean you have active disease. The chest x-ray indicates if you have significant lung infection, but does not show early or very mild infections.
Created for people with ongoing healthcare needs but benefits everyone.
Dr. Pam Yoder
Dr. Pam Yoder commented
Specializes in Maternal-Fetal Medicine
Which tb test?
Jul 10, 2012
Dr. Geoffrey Rutledge
Internal Medicine 42 years experience
Provided original answer
The Mantoux test (PPD, purified protein derivative, tuberculin) is the most accurate and reproducible test. The Tine test also accurate, although some are concerned it is less reproducible.
Jul 10, 2012
Dr. Andrew Ho
Psychiatry 31 years experience
Common mistake BCG: Some people get bacille calmette guerin (bcg), which is a TB vaccine used worldwide (except U.S.) and can cause life-long false positive skin test. Ignorant public health agencies have been known to force TB treatment in such cases. For people who received bcg, TB blood testing is much more specific. You can read about this at the cdc website: http://www.Cdc.Gov/tb/topic/testing/default.Htm.
Created for people with ongoing healthcare needs but benefits everyone.

Similar questions

Canada
A 37-year-old female asked:

Can TB be seen on chest x-ray?

4 doctor answers8 doctors weighed in
Dr. Creighton Wright
surgery 57 years experience
Scar and lesions can: The TB must be seen on histology or culture to be confirmed. Sensitivities are also important for treatment.
Created for people with ongoing healthcare needs but benefits everyone.
Last updated Jun 6, 2018

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