What Happens If a TB Skin Test is Positive?
If a person’s TB Skin Test is positive, the doctor or nurse may prescribe other tests. These tests check if the TB infection is in the lungs. These tests include a chest x-ray and a laboratory analysis of the person’s sputum (phlegm or mucous that is coughed-up). Since TB can occur outside the lungs, other specimen samples such as urine, blood, etc. may be collected and tested. Is Medication Necessary for TB Infection (LTBI)? In the US, physicians typically prescribe Isoniazid (INH) for TB infection. INH reduces the chances of the TB infection (LTBI) turning into TB disease. Once the INH therapy starts, it needs to continue for 9 months. Not following this therapy as prescribed might make the TB bacteria resistant to INH, reducing the drug’s ability to kill the bacteria. This latter issue is a concern if the LTBI turns into TB disease. What Happens If the TB Skin Test is Negative? A person’s negative TB skin test may mean one or more of the following. • Person does not have TB infectio
