Antimycobacterials

Question 1

mechanism of rifampin, rifabutin

Answer 1

inhibit DNA-dependent RNA polymerase

Question 2

Rifampin ____ CYP450 activity, Rifabutin ____ CYP450 activity

Answer 2

speeds up, does not change

Question 3

SEs of rifampin, rifabutin

Answer 3

• hepatotoxicity

- red-orange body fluids

Question 4

mechanism of INH

Answer 4

decreased synthesis of mycolic acids in cell wall

Question 5

INH needs ____ to be converted to active metabolite

Answer 5

bacterial catalase peroxidase (KatG gene) - if under-expressed, can lead to resistance

Question 6

SEs of INH

Answer 6

• hepatotoxicity
• vit B6 def –> peripheral neuropathy, sideroblastic anemia (so give with pyridoxine)
• drug induced SLE
• AG met acid

Question 7

SEs of pyrazinamide

Answer 7

hyperuricemia, hepatotoxicity

Question 8

mechanism of ethambutol

Answer 8

inhibition of arabinosyltransferase which decreases carbohydrate polymerization of mycobacterium cell wall

Question 9

SEs of ethambutol

Answer 9

red-green color blindness

Question 10

Prophylaxis for M. tb.

Answer 10

INH + pyridoxine

Question 11

Treatment of M. tb.

Answer 11

RIPE + pyridoxine

Question 12

Prophylaxis for MAC

Answer 12

azithromycin, clarythromycin, or rifabutin