Antitubercular Drugs

Question 1

What bacteria causes tuberculosis and what is a common synonym for it?

Answer 1

Mycobacterium tuberculosis (MTB)
Tubercule bacilli

Question 2

What is TB most commonly characterized by?

Answer 2

Granulomas in the lung

Question 3

What are signs and symptoms of TB?

Answer 3

Bloody, productive cough for more than 2 weeks
Chest pain
Weight loss and loss of appetite
Weakness and fatigue
Night sweats
Fever

Question 4

What are granulomas

Answer 4

Nodular accumulations of inflammatory cells

Question 5

What are common infection sites of mycobacterium

Answer 5

Mainly the lungs
Cerebral cortex, growing ends of bones, liver, kidney, GU tract and virtually every other tissue and organ in the body

Question 6

What are the 3 sources that transmit MTB?

Answer 6

Infected humans, cows (bovine) and birds (avian)

Question 7

How is tubercule bacilli transmitted?

Answer 7

Droplets expelled by coughing or sneezing gain entry into the body via inhalation.
The infection then spreads to other body organs via blood and lymphatic systems

Question 8

T/F: MTB is a fast growing organism

Answer 8

False: It is a very slow-growing organism

Question 9

What is dormancy in relation to TB?

Answer 9

Pt may test positive for exposure but doesn’t necessarily mean they’re infectious

Question 10

What is the primary infection and the re-infection?

Answer 10

Primary TB is the first infectious episode
The re-infection is the chronic form of the disease

Question 11

Canada has one of the _________ rates of active TB worldwide

Answer 11

Lowest

Question 12

What demographic has the highest incidence rate in Canada?

Answer 12

Indigenous people

Question 13

What percentage of the worlds population does TB affect?

Answer 13

1/3

Question 14

How does TB rank in terms of the number of deaths caused by a single infectious organism?

Answer 14

It ranks 2nd, HIV is 1st

Question 15

What is Multidrug-Resistant TB? (MDR-TB)

Answer 15

TB that is resistant to both isoniazid and rifampin

Question 16

How long do close contacts of patients with MDR-TB need to be treated?

Answer 16

6 to 9 months

Question 17

What is the most widely used antitubercular drug?

Answer 17

Isoniazid

Question 18

Name 4 first-line antitubercular drugs
(RIPE)

Answer 18

Rifampin
Isoniazid
Pyrazinamide
Ethambutol HCL

Question 19

Name 3 second-line antitubercular drugs

Answer 19

amikacin sulphate
levofloxacin hemihydrate
moxifloxacin HCL

Question 20

What are the two phases of antitubercular therapy?

Answer 20

Initial intensive phase with two meds
Continuation phase with three or more meds

Question 21

What drug inhibits protein wall synthesis?

Answer 21

Rifampin

Question 22

What drug inhibits cell wall synthesis?

Answer 22

Isoniazid

Question 23

What drugs use other mechanisms of action?

Answer 23

ethambutol, isoniazid, pyrazinamide

Question 24

What are the adverse effects and contraindications of Isoniazid?

Answer 24

Contraindicated with previous isoniazid-associated liver injury or acute liver disease
Peripheral neuritis
Hepatotoxicity
Hyperglycemia
Discolouration of body fluids

Question 25

What are the adverse effects and contraindications of Ethambutol HCL?

Answer 25

Contraindicated in children under 13 years of age
May cause visual changes such as:
Optic neuritis
Blindness
Altered colour perception

Question 26

What are the contraindications of Pyrazinamide?

Answer 26

Patients with gout and severe liver disease
Not normally used in pregnant patients

Question 27

What are the adverse effects of rifampin?

Answer 27

May experience red/orange/brown discolouration of:
Skin, sweat, tears, urine, feces, sputum, saliva, CSF and tongue
Hepatitis and hematological disorders

Question 28

What is a PPD?

Answer 28

Purified protein derivative
A diagnostic injection given ID in doses of 5 units (0.1mL) to detect exposure to the TB organism

Question 29

How is a positive PPD indicated?

Answer 29

Induration (Hard and big) not erythema at the site of injection

Question 30

What is a BCG injection?

Answer 30

Bacille Calmette-Guerin
Used mainly in first nations communities in the NWT and to vaccinate young children against TB?

Question 31

BCG does not prevent infection but reduces active TB by _____________

Answer 31

60 to 80 %

Question 32

How soon do the effects of drug therapy occur?

Answer 32

Normally within 2 weeks of initiation if the TB strain is drug sensitive

Question 33

How do you prevent the development of MDR-TB?

Answer 33

Perform drug-susceptibility testing on the first mycobacterium species that is isolated from a pt specimen

Question 34

What can you do while waiting for the results of susceptibility tests to prevent the development of MDR-TB?

Answer 34

Begin a regimen with multiple antitubercular drugs to reduce the chances of development of resistance
Adjust regimen after tests results are known

Question 35

What are the 5 things antitubercular therapy effectiveness depends on?

Answer 35

Type of infection
Adequate dosing
Sufficient duration of treatment
Adherence to drug regimen
Selection of an effective drug combo

Question 36

What are the 3 major problems regarding antitubercular therapy?

Answer 36

Drug-resistant organisms
Drug toxicity
Pt nonadherence

Question 37

Therapy may last for up to _________

Answer 37

2 years

Question 38

What is important to emphasize when providing pt education?

Answer 38

Importance of strict adherence to the regimen for improvement of condition

Question 39

What period of illness is contagious ?

Answer 39

The initial period

Question 40

What type of contraceptive does rifampin affect?

Answer 40

It causes oral forms to become ineffective

Question 41

What can be given to combat neurological adverse effects associated with INH therapy?

Answer 41

Pyridoxine (B6)

Question 42

What can be given for peripheral neuropathy resulting from INH?

Answer 42

Vitamin B6