Infection Flashcards
Name 7 clinical markers of infection
- Low BP
- raised blood glucose
- high ESR (erythrocye sedimentation rate)
- high CRP
- high temp
- high RR
- high pulse
what abx are contraindicated/should be avoided in children?
tetracyclines contraindicated in <12yrs
quinolones cause arthopathy
what abx should be avoided in elderly and why?
clindamycin due to high C. diff risk
what abx are nephrotoxic?
what drugs should you avoid in renal impairment (what are the exceptions)?
aminoglycoside, glycopeptide
avoid tetracyclines except minocycline/doxycycline
avoid nitrofurantoin in eGFR <45ml/min
what abx can be hepatotoxic?
what abx needs to be reduced in hepatic impairment?
rifampicin, tetracyclines
reduce metronidazole if severely impaired
what abx can increase risk of cholestatic jaundice?
co-amoxiclav, flucloxacillin
what abx should be avoided in pregnancy ? MCAT QS
metronidazole
chloramphenicol
aminoglycosides
tetracyclines
quinolones
sulphonamides
what abx are most likely to cause antibiotic-resistant colitis and thrush?
clindamycin and broad spectrum abx
what abx to treat staphlococci?
flucloxacillin
what abx to treat MRSA?
vancomycin
what abx to treat streptococci?
benzylpenicllin or phenoxymethypenicillin
what abx to treat anaerobic bacteria?
metronidazole
what abx to treat pseudomonas aeruginosa?
gentamicin
Describe clindamycin (MoA? wide/narrow spec?, bacterostatic or bacteriosidal)
- inhibits protein synthesis
- narrow spectrum
- bacteriostatic
whats the difference between bacteriostatic and bacteriosidal?
bacteriosidal kills bacteria whereas bacteriostatic inhibts growth
what should patients on clindamycin do if they have diarrhoea and why?
stop immediately and see GP - antibiotic associated colitis, c. diff
Describe Linezolid (MoA? wide/narrow spec?, bacterostatic or bacteriosidal)
- inhibits protein synthesis
- narrow spec (only active against gram-positive)
- bacteriostatic
give 2 examples of gram-positive bacteria linezolid is active against?
what’s it an alternative to?
MRSA (alternative to vancomycin), anaerobes
what are the 2 safety warnings you should counsel patients on linezolid on?
- optic neuropathy if used longer than 28 days, counsel pt on signs of visual impairment and new visual symptoms
- blood disorders (thrombocytopenia, anaemia, leucopenia) in those receiving more than 10- 14 days, pre-exisitng myelosuppression, recieivng drugs that may have adverse effects on Hb, blood count, plt function, severe renal impairment - must monitor FBC weekly
what should you do if significant myelosupression occurs whilst on linezolid?
stoptreatment unless considered essential
if a pt has recently been on SSRI, TCA, MAOI and needs linezolid what interval must you leave and why?
leave 2 weeks due to interactions and risk of hypertensive crisis
what class of drug is linezolid?
therefore what must you counsel the pt to avoid?
reversible MAOI
avoid consuming large amount of tyramine
whats the MoA of trimethorprim?
narrow or broad? Bacertiostatic or bactericidal?
inhibits DNA synthesis
narrow spectrum
bactericidal
what the most common indication and dose for trimethoprim?
UTIs
200mg BD
T/F trimethorpim is safe in pregnancy
false - is teratogenic (folate antagonist) in first trimester
in what pt group is trimethoprim contraindiacted (this is also a long term use risk of trimethoprim, pt should be counselled)
blood dyscracsias
counsel on fever, sore throat, rash, mouth ulcers
what does trimethoprim do to potassium
raises it - causes hyperkalaemia
Chloramphenicol MoA? Broad or narrow spec? bacteriostatic or bactericidal?
inhibitis protein synthesis, broad spec, bacteriostatic
is chloramphenicol routinely used?
what are the bad side effects?
no - reserved for life threatening infections
blood dyscrasias and grey baby syndrome so avoid in pregnancy
Metronidazole MoA, broad or narrow? Bacteriostatic or bactericidal?
inhibits DNA synthesis
narrow spec (higher activity againsr anaerobic and protozoa)
bactericidal
why must patients avoid alcohol with metronidazole?
casuses dislfiram-like reaction, will make pt sick
name 4 common SE of metronidazole
GI distrubances, taste disturbance, oral mucositis, furred tounge
Nitrofurantoin MoA? Broad or narrow? Bacteriostatic or bactericidal?
damages bacterial DNA
narrow spec (only urinary pathogens)
bactericidal
can nitrofurantoin be used in pregnancy?
no - neonatal haemolysis