Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

YFRM 300 > Tuberculosis: treatment and prevention > Flashcards

Tuberculosis: treatment and prevention Flashcards

1
Q

what are the goals of Goals of TB treatment

A

Cure the patient of TB
* Prevent transmission of TB to
others
* Prevent the development of
acquired resistance
* Prevent relapse
* Prevent death from TB or its
complications

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Principles of TB treatment

A

Combination Therapy
* Usually, combination tablet
* Intensive and continuation
phase

Period
* Period varies until TB
bacteria are eradicated in
different places

Adherence
* Counselling sessions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Drugs used as treatment for TB

A

isoniazid
ethambutol
pyrazinamide
Rifampicin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

First line TB treatment: mechanisms of action of the drugs

A

Isoniazid (INH /H)
Inhibits synthesis of the mycolic acid layer of the mycobacterial cell wall

Ethambutol (E)
Inhibits synthesis of the arabinogalactan
layer of the mycobacterial cell wall

Pyrazinamide (PZA / Z)
Converted to an acid in the cytoplasm of the mycobacterium, acidify the intracellular environment and
compromise the integrity of the cell
membrane (only effective in dormant mycobacteria)

Rifampicin (Rif / R)
Inhibits mycobacterial RNA synthesis by binding to and inhibiting the

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

site and stage of infection: Rifampicin

A

Bactericidal for intra and extracellular bacteria.
Sterilising activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Drug used foe excellent early bactericidal activity

A

Isoniazid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

site and stage of infection: pyrazinamide

A

Mycobactericidal for intracellular mycobacteria in an acidic
medium.
Most useful during intensive phase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Ethambutol

A

Bacteriostatic (bactericidal at hight doses)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

: monitoring safety of TB treatment

A

Hepatotoxicity monitoring (rifampicin, isoniazid, pyrazinamide).
Monitor liver function: DILI (drug-induced liver injury) * High risk patients: chronic infectious hepatitis, pre-existing liver disease, MDR
TB patients, high levels of alcohol consumption, other hepatotoxic drugs,
HIV+, females and elderly
* Screening for hepatotoxicity: new onset abdominal pain, nausea & vomiting,
jaundice / dark urine
* Check bilirubin and transaminases (5x the upper limit / 3x the upper limit
with jaundice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Management of adverse effect of Rifampicin

A

Side-effect
CI: oral contraceptives
Nausea, GI disturbances
Discoloration of body fluids
(tears, saliva, urine, faeces) orange
/ red
Enzyme induction

take with FOOD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

management of adverse effect of Isoniazid

A

Adverse: Peripheral neuropathy (burning /
pins & needles in feet & legs)

supple with pyridoxine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

management of adverse effect of Ethambutol

A

Optic neuritis

Vision check-ups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

management of adverse effect of Pyrazinamide

A

joint pain (gout), hepatotoxic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Pharmacokinetics: Rifampicin

A
  • Metabolism in the liver – cause
    autoinduction and potent
    enzyme inducer * Elimination: primarily biliaryfaecal route
  • Hepatotoxic
  • Drug-interactions with drugs
    metabolised in the liver * Oral contraceptives & progestin
    implants (replace with injectable
    contraceptives) * Orange/red/brown pigmentation
    of body fluid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Pharmacokinetics Isoniazid

A
  • Distribution: wide including the
    CSF
  • Metabolism in the liver via
    acetylation (slow acetylators at
    greater risk of neurotoxicity) * Inactive metabolites excreted in
    the urine
  • Hepatotoxic
  • Neurotoxic (peripheral
    neuropathy, seizures, psychosis,
    ataxia & optic neuritis) reversed
    by pyridoxine (B6) * Drug-interactions with drugs
    metabolised in the liver (weak
    enzyme inhibitor) * Caution in patients with ep
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Ethambutol

A
  • Distribution: wide not in CSF
  • Metabolism in the liver up to
    15%
  • Mainly unchanged in the urine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

cautions of Ethambutol

A

Cautions: renal failure, in
children under 8 years (visual
symptoms difficult to assess),
hyperuricaemia
* Ocular toxicity – patient selfmonitoring (reading fine print),
monitor: colour discrimination
and visual field

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Pharmacokinetics: Pyrazinamide

A
  • Distribution: wide including the
    CSF
  • Dose-related hepatotoxicity
  • Hyperuricaemia (caused by
    decreased uric acid clearance)
    associated with arthralgia (may
    precipitate gout
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The wanted. outcomes of TB

A
  • Prevent TB transmission
  • Cure with minimal problems
  • Cure with chronic lung disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

The unwanted outcomes of Tb

A

Transmission of TB
* MDR / XDR
* Death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

MDR-TB

A

is a form of tuberculosis that is resistant to at least two of the most potent first-line anti-TB drugs, isoniazid and rifampicin. It poses a significant challenge to tuberculosis control efforts worldwide due to its complexity, prolonged treatment duration, increased costs, and higher rates of treatment failure and mortality compared to drug-susceptible TB.

21
Q

Drug-resistant TB: categories

A

Mono-resistant TB
* Poly-resistant TB
* MDR-TB
* Rifampicin resistant-TB (RR-TB)
* Resistance to at least rifampicin
* Extensively drug-resistant TB (XDR-TB)
* Pre-XDR-T

22
Q

Multidrug resistant

A

MDR In vitro resistance to:
* Rifampicin
* Isoniazid
* With or without resistance to other
anti-TB drugs.

23
Q

XDR (extensively DR)

A
  • MDR TB
  • +
  • In vitro resistance to: * Any fluoroquinolone * AND
  • Any injectable drug
  • Extremely difficult and expensive to treat with a high mortality (90%) in HIV co-infected
24
Q

Isoniazid resistance is caused by

A
  • inhA mutation and
  • katG mutation
25
Q

Drug-resistant TB treatment regimens

A

Short regimen
Pre -2024 – old regimen being phased out:
Short course: * At least 6 drugs used for 9 months. for adults, pregnant and kids> than 6 yrs

2024 – new regimen being phased in: * BPaL-L: * At least 3 drugs used for 6 month. for 6 months

26
Q

Long regimen

A

Long regimen
* 18 months
* Complicated EPTB / extensive
disease on CXR
* Children < 6 years
* Hx of previous treatment with 2nd
line drugs for more than 1 month
* Contact with XDR / Pre-XDR
* Both INH mutations

27
Q

The 6-month BPaL-L regimen;

A

short course
Bedaquiline,
* Pretomanid,
* Linezolid (600 mg)
* With or without levofloxacin (if sensitive)

28
Q

core drugs for long regime

A
  • Bedaquiline, * Linezolid
  • Levofloxacin (substitute if fluoroquinolone resistance) * Clofazimine
  • Terizidone
29
Q

Co-administer pyridoxine to
prevent peripheral neuropathy due to terizidone: dose for adult and children

A

50 mg for adults
25 mg for children

30
Q

Bedaquilline

A

do not use for kids for less than 6 yrs

31
Q

since Bedaquiline is used in kids greater than 6 yrs it is substituted by what drugs

A
  • Delamanid (3 to 6 years) * Para-aminosalicylic acid (less than (<)3 years)
32
Q

The mechanism of action of bedaquiline

A

inhibit mycobacterium ATP synthase
metabolised by CYP3A4 need LFT monitoring (ALT, AST, bili) * DI: CYP3A4 inhibitors / inducers, hepatotoxic drugs
* Major adverse effects: QT prolongation (ECG monitoring – stop if
>500ms) * DI: fluoroquinolones, macrolides, clofazimine, disease

33
Q

The drug that inhibits peptidoglycan synthesis and is widely distributed including CSF

A

Terizidone

34
Q

Major adverse effects of Terizidone

A

Peripheral neuropathy (treat with pyridoxine or amitriptyline) * DI: isoniazid
* Seizures, anxiety, depression, psychosis
* CI: psychiatric disorders / symptom

35
Q

a weak enzyme inducer drug

A

isoniazid

36
Q

which drug causes renal failure and hyperuricemia in children less than 8 years ?

A

Ethambutol

remember it is not given to kids < 8 for TB treatment, affects the optic nerve, not metabolized by the liver that much. and it is bacteriostatic but can kill at high doses.

excreted in urine

inhibit synthesis of arabinogalactan

37
Q

drug that is dose-related hepatotoxicity and widely distributed in the CFS.

A

Pyrazinamide

38
Q

drug that is bactericidal in an acidic medium.

A

Pyrazinamide.

39
Q

extremely difficult and expensive to treat and has a high motility rate in HIV infected patients.

A

extra Drug-resistant.

40
Q

individualized long regimen designed according to who grouping?

A

if Rifampicin-resistant meningitis
if resistant to Bedaquiline, linezolid, pretomanid and cfs

41
Q

Bedaquiline is safe to use in ?

A

above 6 years

42
Q

inhibit peptidoglycan synthesis and is widely distributed including CFS

A

Terizidone

43
Q

Major adverse effects: Terizidone

A

Peripheral neuropathy (treat with pyridoxine or amitriptyline) * DI: isoniazid
* Seizures, anxiety, depression, psychosis
* CI: psychiatric disorders / symptoms

44
Q

adverse effect of clofazimine

A

Adverse effects: common - red/brown pigmentation of conjunctiva and skin and body fluids
* QT prolongation
* DI: fluoroquinolones, macrolides, bedaquiline
* Monitor hepatic function
* Counselling: take with food to diminish GI upset

45
Q
  • Accumulate in tissues: fat, skin, liver, kidneys and reticulo-endothelial cells – cause red-brown pigmentation of conjunctiva and skin; may impart red colour to urine,
    sweat, tears, sputum
  • Eliminated in bile and faeces
A

clofazimine

46
Q

used in children between 3-6 years. substutite of bedaquiline. and has adverse effect of insomia, hallucination, night terrors.

A

delamanid

47
Q

Pretomanid

A

MOA: inhibit bacterial cell wall mycolic acid biosynthesis
* Administered with bedaquiline and linezolid to treat resistant forms
of pulmonary TB
* Major adverse effects: Peripheral neuropathy, acne, anaemia,

48
Q

SYMPTOMS FOR SCREEN

A

Cough (any duration) * Fever * Unexplained weight loss
* Night sweats
* History of previous TB
* Adherence to ART

49
Q
A

YFRM 300 (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions