Firmness: The diameter of the circle of hardened skin at the site of the PPD is measured, and depending upon who you are, what underlying diseases you may have, what medications you are taking, it is read in 48 hrs. Do not measure the area of redness, only the area of firmness (induration). Otherwise there are seldom other symptoms.
Answered 9/28/2016
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A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
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