Antimicrobial resistance Flashcards
Bactericidal
kill bacteria
Bacteriostatic
slow/stop bacterial growth
Types of resistance
- Interference with cell wall synthesis
2.Inhibit protein synthesis - Interference with nucleic acid synthesis
- Disrupt bacterial membrane structure
Interference with cell wall synthesis examples
Beta-lactams (penicillin, cephalosporins, carbapenems)
Glycopeptides (vancomycin, teicoplanin)
Protein synthesis inhibition examples
50s - Macrolides (azithromycin, clarithromycin, erythromycin), chloramphenicol, clindamycin, linezolid
30s - aminoglycosides (gentamycin, amikacin, neomycin) and tetracycline
Interference with nucleic acid synthesis examples
DNA - fluroquinolones (levofloxacin, ciprofloxacin)
RNA - rifampicin
Disrupt bacterial membrane structure examples
polymyxin B and E, daptomycin
Resistance Mechanisms
- Mutation - DNA makes organism resistance, preventing antibx binding
- Enzymes - modify antibx targets
- Efflux - protein pumps eject antibx from inside cell
- Immunity - antibx targets bound by proteins that prevent antibx binding to target site
Plasmids
DNA circles, move between cells
What are Transposons?
small DNA pieces that go into and change DNA
What are Phages?
virus’s that attach germs and carry DNA
Transduction
DNA / RNA is introduces into bacterial cell by virus / vector
Transformation
a bacterium takes up a piece of DNA floating in its environment.
Conjugation
DNA is transferred between bacteria through direct contact between cells, tansfer as a plasmid
Reasons for prescribing antibiotics
- prophylaxis
- empirical therapy
- direct therapy
Causes of resistance
- laboratory - agar
- ecological - regional data trends
- individual patient - review hx
MINDME
M – Microbiology guides therapy
I – Indications should be evidence based
N – Narrowest spectrum required
D – Dosage appropriate to the site and type of infection
M – Minimise duration of therapy
E – Ensure monotherapy in most cases
Start Smart Then Focus
Secondary Care
1. empirical, broad-spectrum antibx initially (based on clinical judgements, most likely causative bacteria, local guidelines / surgical prophylaxis)
2. Take culture
3. Review 48-72hrs - date on chart
4. Swap to narrow spectrum antibx dependent on lab results
5. STOP/SWAP IV to oral
TARGET
Treat Antibiotics Responsibly, Guidance, Education and Tools.
Toolkit designed to support primary care clinicians to achieve and implement antimicrobial stewardship activities
ESPAUR
English Surveillance Programme for Antimicrobial Utilisation Rate
Monitor data for changes in antibx resistance
Reduce inappropriate use of antibx
Reduce consumption of antibx in primary care but increase in secondary care
Impacts on antimicrobial use
- poor clinical outcomes
- increased ADRs
- increase cost
- delay in administration worsens outcome
- wrong dose worsens outcomes
- excess duration increases resistance, increases healthcare associated infections and increases cost
NICE NG15 Antimicrobial Stewardship
- audit
- regular feedback e.g. ADRs, HCAIs
- study resistance
- produce and review guidance
- monitor and evaluate
- education and training
NICE Quality Standards (QS121)
S1:
S2:
S3:
S4:
S5:
S6:
Top Tips for prescribing antibiotics
- broad then narrow
- proper dose
- shortest duration
- IV –> oral asap
- avoid antibx to treat colonisation and contamination
