How to Read a Positive TB Test

TB, or Tuberculosis, is a disease in which bacteria infect and damage the lungs. This disease is characterized by a bad cough, which can produce blood and mucus, weight loss, fever and general weakness. If not treated properly, TB can cause a slew of serious health issues, including death. If you think you have TB, see a doctor immediately so they can perform a TB skin test.

Things You'll Need

• Area of skin where the test has been performed
• Ruler with a millimeter measurement

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Instructions

• 1

  Go to the doctor to get the test performed. The doctor will inject a small dose of a fluid called tuberculin just under the skin. This fluid ultimately tests your body for any TB antibodies which may reside there. If there are antibodies present in your skin, the test will show a positive result.

• 2

  The test should show some results within 2 to 3 days of it being performed. Once the correct amount of time has elapsed, take a look at the skin where the test was performed. If there is no swelling or blisters, the test will be negative. If there is some swelling, you will need to measure the swelling.

• 3

  Look at the skin for signs of blistering. If blistering is present, the odds are that the test is positive. If there is swelling around the test site, measure the length of the swelling. If you are a healthy person, a positive result will be equal or greater than 15-millimeters. However, if you have diabetes or are immunodeficient, the measurement for a positive result will be much less.

• 4

  If you are positive, see a doctor immediately. If the TB is caught in time, a regimen of medication can be taken to battle the disease.