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A 28-year-old female asked:

Dr martin raffi had ppd test last year for immigration request. not sure ppd or tstthey inject into skin. place on my hand red. make tb reactive?

2 doctor answers8 doctors weighed in
Dr. Martin Raff
Infectious Disease 58 years experience
Tuberculosis: No. This is not a sign of reactivation. A positive PPD is determined by the size of the diameter of hardness under the skin at the site of injection in 24 and 48 hrs. The significance of the size will depend upon who you are and your health status and age. The only purpose of the test is to determine whether you have living TB bacteria in your body. They are often inactive.
Created for people with ongoing healthcare needs but benefits everyone.
Dr. Claudia Mikail
Preventive Medicine 26 years experience
PPD (TB skin test): The skin reaction to the PPD Mantoux skin test needs to be a certain size for it to be considered reactive. The cutoffs vary depending on the rest of your medical history. Always request that the person who reads your TB skin test document their findings, with the date it was planted, the date it was read, and the size of induration (if any).
Created for people with ongoing healthcare needs but benefits everyone.
Last updated Mar 16, 2021


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