Antimicrobial Flashcards
What is always resistant to aminoglycosides ?
Streptococci
What are the types of resistance?
Inherent
Accquired
What is always resistant to vancomycin?
Gram negative
Vancomycin can’t enter the cell membrane
What does acquired resistance mean?
It’s present in some strains and not other so laboratory sensitive testing is required.
To test patients specific bacteria
How can resistance be accquired?
Spontaneous
Spread of resistance
What is spontaneous?
Mutation to change structure
How is resistance spread?
Conjugation
Transduction
Transformation
What is conjugation?
Plasmids get copied
Bacteria cells join so plasmid can move through
What is transformation?
Bacteria copy and then releases it out
Uptake of naked DNA by the other bacteria
What is transduction?
Bacterial dna is transferred by a virus (a phage)
How has penicillin resistance come about?
Beta lactamase is produced
Which break the b lactam ring in penicillin which makes it inactive
How to overcome beta lactamase?
Add a beta lactamase inhibitor
Either give both antibiotic drug and inhibitor together»_space; 2 tablets
Or chemically add on the inhibitor to the antibiotic»_space; 1 tablet
What are ESBLs?
Extended spectrum Beta Lactamases
Evolved versions of lactamase enzymes produced by bacteria which gives resistance to cephalosporin and penicillin
Which bacteria produces ESBL?
Klebsiella and E . Coli
Produce UTIs
What is another antibiotics par penicillin facing antibiotic resistance?
Carbapenemase producing enterobacteria
CPE
Carbpenem resistant enterobacteria
CRE
What is carbapenem?
B lactam
Lost of resistance
Not much alternative
Why does b lactam resistant happen?
Beta lactamase produced
Altering PBP
What is PBP?
Penicillin binding protein
This is where beta lactams bind
What resistance mechanism does MRSA have?
Has changed the shape of PBP so lactam ring on penicillin can’t bind to bacteria anymore
Is anything resistant to vancomycin?
Yups vancomycin resistant enterococci
KEEP IT AWAY FROM MRSA
What is normally used for gram positive?
Benzyl penicillin
What is normally used for gram negative?
Amoxicillin
What is co amoxiclav used for?
B lactamase producing coliform.
(This is the mixed b lactamase inhibitor drug)
How should glycopeptides be administered?
Parenteral only
