Question

44. What is not a reason for false-negative TST result? a. Exposed to TB infection 6 weeks ago b. Had TB infection many, many years c. Had an inactivated vaccine 2 weeks ago d. Has a weakened immune system e. Patient is less than 6 months old 45. What is true regarding patient preparations for allergy testing? a. Stop long-acting antihistamines for 5 days before the testing b. Stop all OTC, cold, sleep, and allergy medication 3 days before testing. c. Stop all allergy medications and specific reflux medications 3 days before testing d. All of the above A and B e. 46. What is true regarding the two-step TST testing? a. If the initial TST test is positive, a second test will be given 1 to 3 weeks later. b. Healthcare professionals need a two-step TST test yearly c. If the initial test is negative and the second is positive, the person had a false- negative reaction initially d. All of the above e. B and C What is true regarding blood tuberculin tests? a. Preferred testing for patients who have had the BCG vaccine b. T-Spot TB test is a two-step blood tuberculin test. 47.

Answer 1

44. false negative TST result is when some persons does not react to the tuberculin skin test (TST)

main reasons are

• recent exposure to tuberculosis
• compromised immune system
• early years of age
• very old history of tuberculosis infection
• presence of viral infection
• incorrect method os tuberculin skin test
• incorrect interpretation
• recent administration of live attenuated (activated ) vaccines like measels and small pox

so the answer for not a reason for the false negative result is (C)

45. before doing allergy test patient have to withhold any allergic medication or specific reflux medication 5-3 days before because it may interfere with the result as per doctors order.

no need to stop medications that relieve the symptoms, but should inform the physician about the over the counter medications you are taking.

the answer is (C).

46. two-step tuberculin skin test is conducted if there is a confusion about the first tuberculin test result. that is if the test shows a negative result(may be the false negative result) and doubting tuberculosis exposure the second test may be positive. it should be done 1 to 4 weeks apart. the second tuberculin test also can be done within one year for health care workers is expecting any exposure.

however, if the tuberculin test is positive, need not do the second test. can be diagnosed with chest x-ray and symptoms.

the answer is B and C