Antimicrobials: Antimycobacterials

Question 1

What combination is used to prevent the development of resistant strains of Mycobacterium tuberculosis

Answer 1

combination of rifampin, isoniazid, pyrazinamide, and ethambutol used to prevent development of resistant strains of Mycobacterium tuberculosis

Question 2

What is the mnemonic for the combination of drugs used to prevent the development of resistant strains of Mycobacterium tuberculosis

Answer 2

RIPE (rifampin, isoniazid, pyrazinamide, and ethambutol)

Question 3

What are the 2 phases of treatment for tuberculosis

Answer 3

4 drug combination (rifampin, isoniazid, pyrazinamide, and ethambutol) for 2 months followed by 2 drugs (iosinazid and rifampin) for 4 months

Question 4

Primary TB often presents as

Answer 4

middle lobe cavity

Question 5

______ can be used alone for latent TB therapy

Answer 5

Isoniazid

Question 6

mycolic acids are

Answer 6

essential components of the mycobacterial cell wall

Question 7

How does Isoniazid work

Answer 7

INH acts on the mycobacterial cell wall by inhibiting mycolic acid production

Question 8

How is isoniazid activated

Answer 8

INH is activated by a catalase-peroxidase (KatG)

Question 9

mycobacteria develop resistance to isoniazid by

Answer 9

mycobacteria develop resistance to INH by downregulating Kat G

Question 10

isoniazid side effects include

Answer 10

1. peripheral neuropathy
2. seizures
3. hepatotoxicity
4. asymptomatic rise in aminotransferases
5. Drug induced lupus
6. Anion gap metabolic acidosis

Question 11

How is isoniazid metabolized

Answer 11

INH metabolized by the liver enzyme N-acetyltransferase (slow acetylators have higher risk of side effects)

Question 12

How does isoniazid cause peripheral neuropathy

Answer 12

INH promotes excretion pyridoxine (vitamin B6) –> peripheral neuropathy

Question 13

How is peripheral neuropathy from isoniazied prevented

Answer 13

coadministration of INH and pyridoxine prevents peripheral neuropathy

Question 14

What side effect is associated with all “RIPE” therapy drugs

Answer 14

hepatotoxicity

Question 15

Isoniazid inhibits

Answer 15

cytochrome P450

Question 16

Rifampain activates

Answer 16

cytochrome P450

Question 17

Which RIPE therapy drug activates cytochrome P450

Answer 17

Rifampin

Question 18

Which RIPE therapy drug inhibits cytochrome P450

Answer 18

Isoniazid

Question 19

What does rifampin bind to

Answer 19

rifampin binds bacterial DNA dependent RNA polymerase

Question 20

Rifampin monotherapy is used as?

Answer 20

rifampin monotherapy is used as prophylaxis in close contacts exposed to Haemophilus influenzae or Neisseria meningitidis

Question 21

Rifampin may produce _____ body fluids

Answer 21

rifampin may produce orange body fluids

Question 22

What does ethambutol block

Answer 22

ethambutol blocks arabinosyl transferase, inhibiting carbohydrate formation at the cell wall

Question 23

True or false ethambutol is bacteriostatic?

Answer 23

True: ethambutol is bacteriostatic

Question 24

What are the side effects of ethambutol

Answer 24

1. Optic neuritis with loss of visual acuity and/or red green color blindness
2. hepatotoxicity

Question 25

Pyrazinamide can cause

Answer 25

pyrazinamide can cause hyperuricemia and needle-shaped uric acid crystal formation

Question 26

pyrazinamide may precipitate _____ attacks

Answer 26

pyrazinamide may precipitate gout attacks

Question 27

Mycobacterium avium complex (MAC) includes

Answer 27

Mycobacterium avium, and Mycobacterium intracellulare

Question 28

Mycobacterium avium complex (MAC) infections are treated with

Answer 28

a macrolide (azithromycin or clarithromycin) combined with ethambutol

Question 29

Mycobacterium avium complex (MAC) infections are a common cause of _______ in aids patients

Answer 29

MAC is a common cause of disseminated disease in AIDS patients

Question 30

Macrolide prophylaxis is used for Mycobacterium avium complex (MAC) infection when

Answer 30

macrolide prophylaxis for MAC when CD4 < 50

Question 31

What may be added as a third agent in the treatment of Mycobacterium avium complex (MAC) infections

Answer 31

Rifabutin

Question 32

____ and ______ activate cytochrome P450

Answer 32

rifampin and rifabutin

Question 33

_____ _____ is the causative agent of leprosy

Answer 33

Mycobacterium leprae

Question 34

What drug is used to treat leprosy

Answer 34

Dapsone

Question 35

Dapsone is used to treat

Answer 35

leprosy

Question 36

Dapsone can cause

Answer 36

1. agranulocytosis | 2. hemolytic anemia in G6PD deficiency

Question 37

In patients with leprosy bite cells and Heinz bodies are seen in

Answer 37

bite cells and Heinz bodies seen in RBCs

Question 38

dapsone can cause ______ in G6PD deficiency

Answer 38

hemolytic anemia

Question 39

Clofazimine treats

Answer 39

lepromatous leprosy

Question 40

What drug is used for lepromatous leprosy

Answer 40

Clofazimine

Question 41

______ is seen in lepromatous leprosy

Answer 41

leonine facies

Question 42

Rifampin is used to treat

Answer 42

1. Leprosy | 2. TB

Question 43

What are the 3 uses of rifampin

Answer 43

1. To treat leprosy 2. To treat TB 3. Prophylaxis for exposure N. Meningitidis or H. Influenzae