Antimicrobial therapy Flashcards
What are the 4 quadrants?
G+ve aerobes
G - ve aerboes
obligate anaerobes
penicillinase producing staph
What are the atypical bacteria?
rickettsia borrelia mycoplasma bartonella chlamydia mycobacterium
G +ve aerobe example and what has no activity?
strep
enterococci
aminoglycosides
meronidazole
What works for g+ve aerobes?
penicillin G aminopenicillins cephalosporins lincosamides / macrolides tetracyclines rifampin (fluoroquinolones)
G -ve example and what has no activity?
e.coli
pasturealla
pseudomonas
helicobacter
metronidazole
penicillin G
lincosamides / macrolides
what works for g-ve aerobes?
fluoroquinolones aminoglycosides 2nd/3rd generation cephalosporins ticarcillin - clavulante (amoxy - clav)
obligate anaerobes example and what has no activity?
clostridia
fluoroquinolones
aminoglycosides
what works for obligate anaerobes?
penicillin G amoxy-clav clindamycin metronidazole chloramphenicol rifampin
penicillinase producing staph example and what has no activity?
s.pseudointermedius
penicillin G
aminopenicillins
metronidazole
what works for penicillinase producing staph?
amoxy-clav 1st / 2nd gen cephalosporins cloxacillin fluoroquinolones rifampin (clindamycin)
When to use ABX?
- agent been diagnose / likely with the data
- believed to progress without therapy
- would cause critical illness if it occured
- heat , swelling, pyrexia, systemic signs, neutrophilia
When not to use ABX?
- for every problem / dont know what else to do
- vomiting without diarrhoea
- haematuria in cats under 10 YO
- blood in faeces (unless pathogen caused)
What bug is most common on skin? urinary tract? liver? GIT? bronchi? pneumonia? cat? horse?
skin - staph UT - e.coli from gut / staph from skin liver - from GIT GIT - G-ve anaerobes bronchi - bordatella pneumonia - anything cat - mycobacteria in skin wounds horse - strep common
What is MIC?
minimum inhibitory concentration
the lowest conc of a drug that will inhibit bacterial growth
What are the 4 main classes of ABX?
inhibit cell wall synthesis
inhibit cell membrane function
inhibit protein synthesis
inhibit nucleic acid synthesis
Pharmacokinetics of bacteriostatic drugs?
drug conc. stay above MIC
pharmacokinetics of bacteriocidal drugs?
time dependent - time over MIC predicts success
conc dependent - peak conc predicts success
What are hard to access areas?
brain eye prostrate bronchus mammary gland intracellular bacteria poorly vascularised tissue
How is penetration improved?
more lipophilic
when is surgical ABX prophylaxis needed?
- shocked or emaciated or endocrinopathies
- emergency procedure
- use of implants
- over 90 min surgery
- contaminated surgery
- patients with leukopenia
- consequences of inf would be disastorous
What do you never give to egg laying birds?
enrofloxacin (baytril)
Never give to food animals?
chloramphenicol
metronidazole
phenylbutazone
