antibiotics symposium 2: what to choose? Flashcards
how do beta lactams work and which types of bacteria are they especially good for?
bind to penicillin binding proteins - G+ bacteria, but also work for G- bacteria
What antibiotic is used for group A strep in the throat?
Penicillin V
which antibiotic can be used for Strep. penumoniae?
Amoxicillin
which of the beta lactams would be suitable for G- bacteria?
co-amoxiclav piperacillin-taxobactam (tazocin) meropenem cefuroxime ceftriaxone cefotaxime
why are cephalosporins used?
good for people with a penicillin allergy
better for more resistant bugs
get into different parts of the body eg the CNS
what kind of infections do G+ bacteria cause?
skin infections
chest
throat
what kind of infections do gram - bacteria cause?
urine
gallbladder
abdominal infections
infectious diarrhoea
Give examples of G+ skin infections
Staph. aureus
strep pyogenes
Give an example of a gram positive chest infection
Strep pneumoniae
give examples of G+ throat infections
group A strep (pyogenes)
give examples of G- infectious diarrhoeal infections
shigella
salmonella
give examples of glycopeptides
vancomycin and teicoplanin
when would you use the glycopeptides?
MRSA
penicillin allergy
given the glycopeptides are cell wall killers what type of infections would you use it for?
G+ ones eg chest, throat and skin infections
how do the macrolides work?
affect protein synthesis
give examples of macrolides
clarythromycin and erythromycin
how do the lincosamides work?
affect protein synthesis
give an example of a lincosamide
clindamycin
what are macrolides used for?
G+ and atypical pneumonias
what are lincosamides used for?
G+ staph aureus, Group A strep and anaerobes
when can you use clindamycin?
in cellulitis if allergic to penicillin or in necrotising fasciitis (turns off toxins produced by bacteria)
is it easier to develop resistance to proteins or to cell wall antibiotics?
proteins - so resisitance to macrolides is higher than beta lactams
give an example of a tetracycline?
doxycycline
when is doxycycline used?
G+ but broad spec
can be used in cellulitis if there is a penicillin allergy and chest infections
so overall what classes of antibiotics can you use for G+ infections?
beta lactams macrolides lincosamides tetracyclines glycopeptides
What are the antibiotics that can be used for G- infections?
ciprofloxacin
tripmethoprim
nitrofurantoin
‘high up’ beta lactams (like cephalosporins and carbapenems)
what infections can ciprofloxacin be used for?
urinary tract infections, gallbladder infections, abdominal infections
what is trimethoprim and nitrofurantoin used for?
UTIs
what is a negative side effect of ciprofloxacin?
C. diff
what enzyme are G- bacteria good at making?
beta lactamases
what are the commonest cellulitis causing bacteria?
group A strep
staphylococcus
what antibiotic is more ‘streppy’
amoxicillin
can flucloxacillin target staph and strep?
yes
how is amoxicillin administered?
orally
