Treatment of TB

Question 1

Are norcardiform bacteria gram positive or negative?

Answer 1

Positive

Question 2

What was the first antibiotic cure for TB?

Answer 2

Streptomycin

Question 3

What is the mechanism of action of streptomycin?

Answer 3

Binds to the ribosome - inhibiting protein synthesis

Question 4

What is first line therapy for the treatment of TB?

Answer 4

Isoniazid

Question 5

Mycobacteria cell wall is rich in _____ acid

Answer 5

mycolic

Question 6

Isoniazid is a prodrug. True or false?

Answer 6

True - for isonicotinamide

Question 7

What is the mechanism of action of isonicotinamide?

Answer 7

Inhibits the biosynthesis of mycolic acid needed in the cell wall of M.tb

Question 8

Isoniazid is used as monotherapy. True or false?

Answer 8

False - never used alone due to resistance being rapidly acquired

Question 9

What is the mechanism of action of rifamycin?

Answer 9

Inhibits RNA and hence protein synthesis

Question 10

How does ethambutol work?

Answer 10

Inhibits formation of mycobacterial cell wall by inhibiting arabinosyl transferase which means synthesis of arabinogalactan in the cell wall is inhibited

Question 11

Optic neuritis is the main side effect of which drug?

Answer 11

Ethambutol

Question 12

Pyrazinamide is a prodrug. True or false?

Answer 12

True

Question 13

Pyrazinamide is contraindicated in pregnancy. True or false?

Answer 13

False - safe to use everywhere apart from USA

Question 14

How does pyrazinamide work?

Answer 14

Prodrug converted to pyrazinoic acid which is thought to inhibit fatty acid synthase 1, which is needed for synthesis of mycolic acid