After 48 to 72 hours, the forearm is observed for any redness or swelling at the sit of the injection. If no redness or swelling appears, it's a negative test. The skin is inspected for redness, hardening or thickening of 10 millimeters or more. If present, the test is considered positive. A positive Mantoux test may not mean active TB infection, but means exposure to the bacteria.
Any positive test means additional testing by a physician is necessary.
Individuals who previously have had a positive Mantoux test or had TB, shouldn't have the Mantoux test. Periodic chest X-rays are used by the physician for evaluation. If you'd like further information on the Mantoux test, consult your physician. Site Map Use of this site signifies your agreement to the Terms of Use . This site is presented for information only and is not intended to substitute for professional medical advice.