TB

Question 1

What are some of the tests done for suspected pulmonary TB?

Answer 1

1. Tuberculin skin test (TST)
2. TB blood test: Interferon gamma release assays (IGRA)
3. Chest X Ray

Others may include:
- suptum testing
- culture
- molecular assays
- microscopy

Question 2

List at least 3 advantage of IGRA over TST test

Answer 2

• TB specific
• No cross activity with BCG vaccination
• 24 hour turn around
• single visit to clinic

(due to cost, TST remains the most preferred method for latent TB infection)

Question 3

What is a widely used (cheap and quick) way to diagnose TB?

Answer 3

Sputum smear / microscopy
However, has poor sensitivity

Question 4

What is the gold standard in TB diagnostics

Answer 4

Sputum cultures
However very slow, can take 1 to 8 weeks to provide results, sensitivity 82%

Question 5

TST and IGRA is only used for ____ TB

Answer 5

Latent TB

Question 6

What causes TB

Answer 6

Mycobacterium tuberculosis (acid-fast bacili)

Question 7

List 3 groups of people which are more susceptible to progression to active TB disease

Answer 7

1. Immunocompromised
2. Elderly
3. HIV positive patients

Question 8

____ therapy must be avoided in active TB

Answer 8

Monotherapy

Question 9

What is Mono-resistance?

Answer 9

Resistance to one first-line anti TB drug only

Question 10

What is poly-resistance?

Answer 10

Resistance to more than one first-line anti TB drug only

Question 11

Resistance to both isoniazid and rifampicin is known as ____

Answer 11

Multidrug resistance