Transmission and Pathogenesis of TB Exam

1. The Mantoux tuberculin skin test (TST) is given by using a needle and syringe to inject 0.1 ml of 5 tuberculin units of liquid tuberculin between the layers of the skin (intradermally), usually on the forearm.

2. The presence of erythema (redness) at the site of the skin test injection indicates that a person has TB infection.

3. From 1993 through 2013, there was a steady decline in the number of TB cases reported annually in the United States.

4. People with symptoms of TB should NOT be evaluated for TB disease if they have a negative TST or interferon-gamma release assay (IGRA) result.

5. Extrapulmonary TB occurs in the lungs.

6. The current classification system for TB is based on the pathogenesis of TB.

7. A person who has latent TB infection, but not TB disease, is infectious to others.

8. The risk of developing TB disease is highest in the first 2 years after infection.

9. LTBI is detected by the tuberculin skin test (TST) or an interferon-gamma release assay (IGRA).

10. The results of the chest x-ray alone can be used to confirm that a person has TB disease.