d) Mechanisms of resistance
State the mechanism of resistance that may develop with the drugs used. (4 marks)
I think that listing out general mechanisms of resistance would be fine.
General mechanisms of resistance (applies to antibiotics generally)
- Mutation of the antibiotic target
- Mutation of the bacterial enzyme required to activate the antibiotic
- Enzymes which can breakdown the antibiotic
- Efflux pumps which can pump the drug out of the bacterium.
Specific mechanisms of resistance:
- Mutation of RNA polymerase causing reduced binding
- Resistance occurs rapidly if used as monotherapy
- Underexpression of enzyme required to convert drug into active metabolite
- Increased production of arabinosyltransferase
- Efflux pumps
- Mutation of the enzyme required to convert pyrazinamide into active compound.