Flashcards in Topic 19 Deck (52):
“Minimum INHIBITORY Concentration” shows level of no growth but bacteria can still be alive
“Minimum BACTERIOCIDAL Concentration” shows level at which 99.9% of bacteria is killed
keeps a static level of bacteria (curve plateaus)
kills bacteria (curve plummets)
describe gram positive
thick peptidoglycan membrane
describe gram negative
thin peptidoglycan membrane covered by outer membrane so they are "harder" to kill
how do Penicillins & Cephalosporins (β-Lactam antibiotics) work?
Prevent bacterial cell wall peptidoglycan cross-linking so newly produced bacterial cell walls are “weak” and the bacteria “fall apart”
•These antibiotics are “cidal”
β-lactamase is a significant source of what?
antibiotic resistance among microbes
“First Generation” Penicillins are effective against what?
gram-positive organisms (particularly Strep)
gram negative cocci
and a few others,
which penicillin is the archetype
Anti-staphylococcal Penicillins drug names (3)
Broad-Spectrum Penicillins drug names (2)
what is the DRUG OF CHOICE for pre-cardiac surgery dental prophyllaxis!
Antipseudomonal Penicillins drug names (3)
Antipseudomonal Penicillins are used for what?
what is Pseudomonas aeruginosa
a very problematic, very pathogenic gram negative that readily develops resistance to antibiotics
--causes blue/green pus
what drug also has a β-lactam ring like the penicillins but no antimicrobial activity.
Clavulanic acid (CA)
what does Clavulanic acid (CA) do?
CA is a suicide inhibitor of bacterial β-lactamase that attaches to and permanently deactivates the enzyme.
what drugs are Clavulanic acid (CA) combined with?
amoxicillin (Augmentin) OR ticarcillin (Timentin)
what will happen to a patient with inflamed meninges if you give them penicillin
inflamed meninges are more permeable to penicillin so it will cross the blood brain barrier
what category of antimicrobial are commonly used in open heart surgery and as part of the “prime”
1st Generation Cephalosporins drug name
2nd Generation Cephalosporins drug names (3)
Vancomycin targets what type of microorganism
Spectrum of activity limited to gram positives
Vancomycin is Reserved for use in
MRSA, Methicillin Resistant Staph epidermidis (MRSE) and enterococcal infections.
if Aminoglycosides end in “…mycin” they’re from what?
if Aminoglycosides end in “…micin” they’re from what?
how do Aminoglycosides work?
Interfere with bacterial protein synthesis by binding to bacterial ribosomal 30S subunit…
*This action is “cidal”
Aminoglycosides spectrum of activity limited to what?
gram negative bacteria, such as E. coli, Proteus mirabilis, and Pseudomonas aeruginosa
Aminoglycosides exhibit a _____ effect when used with pens, cephs, and vancomycin for resistant bacteria
Aminoglycosides exhibit concentration-dependent killing- which is what?
Increasing concentrations of aminoglycosides kill increasing proportions of bacteria at increasing rates
Aminoglycosides: Unlike other drugs discussed, aminoglycosides exhibit poor ...
CNS penetration even in the presence of meningitis
Aminoglycosides drug names (4)
which Aminoglycosides is rarely used and has lots of resistance
which Aminoglycosides has the LEAST bacterial resistance
All aminoglycosides cross what?
the blood/placenta barrier and concentrate in fetal tissue!
Aminoglycoside Toxicity results in what?
#1) Ototoxicity: vestibular &/or cochlear
#2) Neuromuscular Paralysis PARTICULARLY with myasthenia gravis patients
#3) Nephrotoxocity ranging from mild to total renal destruction
which Aminoglycosides is used only topically (too nephrotoxic)
which Aminoglycosides was first produced. LOTS of microbial resistance has developed