Antimicrobial Resistance Flashcards
What is a biofilm?
A thin robust layer which a community of bacteria can attach to, causing organisms to be more resistant to antibiotics
What are persistor cells?
Metabolically inert, non dividing cells that exhibit multidrug resistance and can resist all known antimicrobials
Why are persistor cells resistant to antibiotics?
Antibiotics usually act through corrupting active processes however these cells are dormant and metabolically inert.
What’s the difference between cross resistance and multi resistance?
Cross resistance is when an organism is resistant to closely related antibiotics by a single mechanism
Multi resistance is resistance to unrelated antibiotics through multiple mechanisms
How can microbial cells pass on resistance to other cells?
Horizontal gene transfer
What are some mechanisms of resistance?
- Not allowing antimicrobial into cell
- Removing antimicrobial through pumps
- target mutation
- drug modification
- drug degradation
- over production of target mimic
- beta lactamase production
Examples of beta lactamase inhibitors?
- clavulanic acid
- tazobactam
Two kinds of beta lactamases?
- penicillinase
- cephalosporinase
Examples of natural resistance?
- target not present
- target not accessible (Gram +ve antibiotic trying to enter gram -ve bacteria)
- metabolism
- spores, biofilm, persistor cells
What is appropriate prescribing?
- using narrow spectrum antibiotics wherever possible to prevent resistance
- does the patient really need the antibiotic
- prescribe the necessary but not for the sake of it
Antibiotics on the WHO watch list?
-Temocillin
- piperacillin/tazobactam
- cephalosporins (except first gen)
- carbapenems
- vancomycin
- macrolides
-fluoroquinalones
Alternative therapies to prescribing antibiotics?
- vaccination
- antibody therapy
- anti infective drugs
- probiotics
-phage therapy
What can happen if you unnecessarily prescribe ?
Resistance is more likely
