TB drugs- Allman

Question 1

define multidrug-resistant (MDR) TB

Answer 1

• resistant to at lead INH AND RIF

Question 2

what are MDR patients at high risk for

Answer 2

-treatment failure and further acquired drug resistance

Question 3

what happens to patients with just strain resistant to RIFAMPIN alone

Answer 3

• better prognosis

- increase risk for treatment failure

Question 4

What is extensive drug Resistant (XDR) TB

Answer 4

• MDR TB plus resistance to FQN
• AND resistant to at least one other of the 3 injectable drugs
• amikacin
• kanamycin
• capreomycin

Question 5

what defines therapeutic failure

Answer 5

positive sputum coherent scattering after 4 months of compliant therapy

Question 6

what is the dosing guideline for TB drugs

Answer 6

• daily dosing
• twice or thrice weekly dosing
• Directly observed therapy

Question 7

MOA for Rifampin

Answer 7

inhibits DNA-dependent RNA polymerase
- suppression of initiation of chain formation in RNA synthesis

Bactericidal: kills slow-growing mycobacteria present within macrophages and in caseating granulomas

Question 8

where is Rifampin distributed

Answer 8

CNS
tuberculosis abscesses
intracellular sites

Question 9

How is Rifampin metabolized

Answer 9

deacetylation

• autoinductin of metabolism occurs
• Rifampin Revs up Liver

Question 10

3 major adverse effects of Rifampin

Answer 10

• transient elevation in serum transaminases
• hepatotoxicity
• orange discoloration ( sweat, tears, urine)
• Rifampin revs up and red

Question 11

Drug interaction of Rifampin

Answer 11

• increase in cytochrome P-459
• increases metabolism of
• warfarin
• narcotics
• steroids ( oral contraceptives)

Question 12

place in therapy: Rifampin

Answer 12

• treats active TB

- 2nd line agent for preventative therapy

Question 13

MOA for Isoniazid ( INH)

Answer 13

inhibits synthesis of mycolic acid

Question 14

metabolism of Isoniazid

Answer 14

acetylation

Question 15

Rate of acetylation of Isoniazid depend son what

Answer 15

genes: can be slow or rapid acetylator

Question 16

Adverse effects of Isoniazid

Answer 16

• transient elevation in serum transaminases
• hepatotoxicity
• Neurotoxicity

Question 17

who is neurotoxicity seen in with Isoniazid, treatment?

Answer 17

• alcoholics, homeless

- Pyridoxine ( B6)

Question 18

MOA for Pyrazinamide

Answer 18

• not well known

- toward dormant organism

Question 19

Adverse effects of Pyrazinamide

Answer 19

Hepatotoxicity

hyperuricemia : decreased renal excretion of uric acid, bad for gout patients

Question 20

MOA for Ethambutol

Answer 20

not well known

bacteriostatic

Question 21

how is Ethambutol excreted

Answer 21

urine

Question 22

Adverse effects of Ethambutol

Answer 22

optic neuritis ( retrobulbar neuritis)
-decrease visual acuity and red-green color blindess

Question 23

Ethambutol should be used with caution in what patient group

Answer 23

children

Question 24

MOA for Streptomycin

Answer 24

Aminoglycoside antibiotic

- inhibit protein synthesis

Question 25

how is streptomycin absorbed and administered

Answer 25

poorly absorbed in GI tract

- given IM or IV

Question 26

Adverse effects of Streptomcin

Answer 26

nephrotoxicity

impairment of 8th cranial nerve function

Question 27

which is better ethambutol or streptomycin

Answer 27

ethambutol

Question 28

when can you not give rifabutin

Answer 28

• unacceptable interactions with Rifampin

- or intolerance to Rifampin

Question 29

Adverse reactions for Rifabutin

Answer 29

rash
GI
NEUTROPENIA

Question 30

who can receive Rifapentine

Answer 30

HIV negative

- non-cavitary, drug susceptible pulmonary tuberculosis

Question 31

what is the most widely used antilieprosy agent

Answer 31

Clofazaime

Question 32

MOA of Clofazaomine

Answer 32

binds preferentially to mycobacterial DNA causing inhibition of transcription

Question 33

Adverse effects of Clofazamine

Answer 33

• GI
• severe and life threatening abdominal pain and organ damage caused by crystal deposition
• discoloration of skin and eyes

Question 34

how long is general treatment for TB

Answer 34

6 months

Question 35

how long is treatment for osteo/miliary/meningitis

Answer 35

12-24 months

Question 36

if a TB patient has renal failure what should you avoid

Answer 36

Streptomycin
Kanamycin
Capreomycin

Question 37

TB children should avoid what medicine

Answer 37

Ethambutol

Question 38

when is suspected treatment failure seen

Answer 38

• lack of clinical progression 6-8 wks into therapy

- add 2 or more new TB agents

Question 39

treatment for Mycobacterium leprae should include

Answer 39

Dapsone
Rifampin
Clofazimine
DR. C

Question 40

MOA for Dapsone

Answer 40

competitive inhibitor of folic acid synthesis

Question 41

what are 2 major categories for Leprosy

Answer 41

1. lepromatous - disseminated

2. Tuberculoid - localized

Question 42

How is leprosy transmitted

Answer 42

prolonged contact

Question 43

how long is drug course of leprosy

Answer 43

2-5 years

Question 44

what are symptoms for MAC

Answer 44

fever
night sweats
weight loss
anemia

Question 45

Who does MAC usually occur in

Answer 45

HIV less than 100 CD4

Question 46

when is primary prophylaxis recommended for HIV MAC

Answer 46

CD4 less than 50

Question 47

How do non-HIV patients present with MAC

Answer 47

in lungs

chronic productive cough

Question 48

prophylaxis regimen for MAC

Answer 48

Clarithromycin
Azithromycin
Alternative Rifabutin if above2 not tolerated

Question 49

Treatment regimen for MAC

Answer 49

at least 2 agents

• Clarithromycin or Azithromycin plus Ethambutol
• consider adding one of the following: Clofazamine, Rifampin, Rifabutin or Cipro

Question 50

how long is RIPE regiment

Answer 50

6 months total

• 2 months RIPE
• 4 months RI

Question 51

how long is RIP regiment

Answer 51

6 months total

• 2 months RIPS
• 4 months RI

Question 52

which drug is more active against MAC

Answer 52

Clarithromycin