Antibiotics Flashcards
Bactericidal
kill organism
Bacteriostatic
inhibit the growth and proliferation of the organism allowing the body’s defenses to kill the organism itself
Minimum inhibitory concentration (MIC)
lowest antimicrobial concentration that prevents visible growth of an organism after 24H of incubation in a growth medium
clinical standard
Minimum bactericidal concentration (MBC)
lowest antimicrobial concentration that kills 99.9% of the original amount of infectious cells
more predictive than MIC
Postantibiotic effect (PAE)
sustained suppression of an organism’s growth after a brief exposure to an antibiotic
allows for less frequent dosing while sustaining clinically significant levels of antimicrobial activity
What approach should you use when selecting antibiotic treatment
use a systemic approach starting with the narrowest spectrum possible and continuing to narrow the spectrum as much as possible throughout
consequences of not utilizing a systemic approach
increased toxicity
increased cost of therapy
widespread resistance
superinfections
classification of antibacterial drugs according to mechanism of action
inhibitors of cell wall synthesis
inhibitors of protein synthesis
inhibitors of metabolism and nucleic acid synthesis
inhibitors of cell membrane function
Most common gram negative bacteria
acinetobacter escherichia coli hemophilus klebsiella proteus pseudomonas aeruginosa
Common gram positive bacteria
enterococcus
staphylococcus
streptococcus
clostridium (becoming more common)
Gram positive versus gram negative
gram positive - thick peptidoglycan layer –> retains purple stain
gram negative - thin peptidoglycan layer + lipopolysaccharide layer –> more difficult for stain to penetrate –> pink color
gram negative tend to be more difficult to treat
