Antimicrobial Stewardship and Resistance Flashcards
What is an antibacterial?
Something that acts only to kill bacteria but includes all compounds including antibiotics and antibacterial handwash, disinfectant ect.
What is antibiotic?
Natural and synthetic compounds that are active against bacteria and have been liscenced for use to treat infections
What is antibiotic resistance?
The ability of bacteria to protect themselves against the effects of an antibiotic.
Laboratory phenomenon- Resistant bacteria will multiply in the presence of antibiotics on a petri dish.
What is clinical antibiotic resistance?
The baceria can grow in the antibiotic concentrations reached in the body during therapy resulting in treatment failure and an antibiotic resistant infection
What is resistant and susceptible bacteria?
Resistant = Antibiotic will not inhibit bacterial growth at clinically achievable concentrations Susceptible = Antibiotic will inhibit bacterial growth at clinically achievable concentrations.
What is MDR?
Non susceptibility to at least 1 agent in 3 or more antimicrobial categories.
What is XDR?
Non susceptibility to at least one agent in all but 2 or fewer antimicrobial categories
What is PDR?
Pan drug resistance: non susceptibility to all agents in all antimicrobial categories
Resistance is either innate or acquired. Which type of resistance can good prescribing reduce?
Acquired resistance
Is it normal to have resistant bacteria in the gut microbiome?
Yes its variation- normally there is no reason for them to replicate or transfer their DNA. Just die
How is antibiotic resistance acquired?
Vertical transmission (random mutation)
Horizontal transmission. (3 methods)
ALL increases the resistance of the microbiome- only a problem if that infects a sterile site
What are the 3 methods of horizontal transmission of resistance?
1) Transformation- bacteria scavenge resistance genes form dead bacterial cells and integrate them into their genome
2) Transduction- When resistance genes are transferred by bacteriophages (virus’ that infect bacteria)
3) Conjugation- when genes are htransferred on plasmids between bacterial cells through tubes called pilli.
What are the resistance mechanisms which bacteria use?
1) Inactivation of antibiotics
2) Impermiability to antibiotics
3) Efflux of antibiotics
What percentage of health care associated infections are caused by resistant organisms?
25%
Where does most antibiotic prescribing occur?
Communities.
High income countries still use more antibiotics per capitia than low and middle income countries
