Tuberculosis: Treatment and prevention 3 Flashcards
MoA for clofazimine
Membrane destabilisation
Reactive species
MoA for PAS
Mycobactin (decreased iron uptake)
Inhibition of folic acid synthesis
MoA of Bedaquiline
ATP synthase
MoA of ethambutol
Cell wall sythesis
MoA of meropenem imipenem amoxicillin, clauvulanic acid and cycloserine terizidone
Inhibition of peptidoglycan synthesis
MoA of isoniazid
Protiomide
Ethionamide
Mycolic acid biosynthesis
MoA of PA-824 Delamanid
Reactive species a
Mycolic acid biosynthesis
MoA of moxifloxacin
Gatilofloxacin
Ofloxacin
DNA gyrase
MoA of rifampicine and rifabutin
Inhibition of RNA synthesis
MoA of linezolid, sutezolid AZD5847, Amikacin, kanamycin, capreomycin, clarithromycin
Ribosome-inhibit protein synthesis
Bedaquiline increases risk of what?
Increased risk of mortality
MoA of bedaquiline
Ihibits mycobacterial ATP synthase
Pks of bedaquiline: metabolism
PKs: metabolised by CYP3A4 need LFT monitoring (ALT, AST, bili)
DI for dedaquiline
DI: CYP3A4 inhibitors / inducers, hepatotoxic drugs.
DI: fluoroquinolones, macrolides, clofazimine, diseases
Major adverse effects of bedaquiline
Major adverse effects: QT prolongation (ECG monitoring – stop if
>500ms)
MoA od terizidone
MOA: Inhibits peptidoglycan synthesis
Distribution of Terizidone
- Widely distributed including CSF
The major effects and DI for Terizidone
Major adverse effects:
* Peripheral neuropathy (treat with pyridoxine or amitriptyline)
* DI: isoniazid
* Seizures, anxiety, depression, psychosis
* CI: psychiatric disorders / symptoms
Pks of clofazimine
- Pharmacokinetics:
- 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
Adverse effects of Clofazimine and DI
Adverse effects: common - red/brown pigmentation of conjunctiva and skin
and body fluids
* QT prolongation
* DI: fluoroquinolones, macrolides, bedaquiline
what to monitor when using clofazimine
Monitor hepatic function
counselling for clofazimine
- Counselling: take with food to diminish GI upset
Delamanid is used for which age group and monitor what?
Children 3-6 years (monitor for neuropsychiatric adverse effects:
insomnia, hallucinations, night terrors)
Major advese effects of Delamanid and DI and counselling
Major adverse effects:
* Common, nausea, vomiting and dizziness
* QT prolongation (discontinue if QTcF is >500ms or ventricular
arrhythmia)
* DI: fluoroquinolones, macrolides, bedaquiline, clofazimine
* DI – hepatotoxic drugs & CYP3A4 inhibitors
* Counselling: take with food to diminish GI upset
MoA of pretomanid
MOA: inhibit bacterial cell wall mycolic acid biosynthesis
List drugs to treat resistant forms of pulmonary TB
Pretomanid
Bedaquiline
Linezolid
Major adverse effects of pretomanid
Major adverse effects: Peripheral neuropathy, acne, anaemia,
DI for pretomanid
DI: Avoid alcohol and hepatotoxic agents, strong or moderate CYP3A4
inducers, including herbal supplements
Explain the TB chemoprophylaxis
TB test and treat approach: offering either TPT or active TB
treatment
to achieve TB elimination, it is imperative to implement TPT more
comprehensively for everyone with significant TB exposure and all
other individuals at high risk of TB.
In most instances, people who should be offered TPT will share a
household with at least one person who is concurrently on TB
treatment. Therefore, where possible, a ‘family-centred’ approach to
TPT initiation and adherence support should be adopted
TPT and IPT stands for what
Abbreviations
* Tuberculosis preventive therapy (TPT)
* Isoniazid preventive therapy (IPT)
It is important to rule out TB disease before initiating which TB chemoprophylaxis
TPT
All people considered for TPT should undergo what?
All people considered for TPT should undergo clinical evaluation
(symptom check and physical examination - CXR) and be tested with
GeneXpert (Xpert), even if asymptomatic.
List peole who acquire TPT
TB contacts: All adults, adolescents and children (including newborns or
infants) exposed to TB require TPT ,once T.B disease has been excluded
through evaluation - irrespective of HIV status, pregnancy, or previous TB
disease or treatment status. Significant TB exposure can occur in any
setting, e.g. in the household, workplace, place of learning or care, or
other.
* People living with HIV: All adults, adolescents and children including
infants living with HIV (irrespective of a known significant TB exposure)
should receive a course of TPT once TB disease has been excluded through
testing. People newly diagnosed with HIV should always be tested for TB
prior to initiating antiretroviral treatment (ART).
* Inmates in correctional facilities after ‘significant TB exposure’
* Healthcare workers
* People who previously had TB after ‘significant TB exposure’