Spotlight Lectures Weeks 1-6 (Midterm) Flashcards
What are the 4 mechanisms of antibiotic resistance?
1) Modifications of the Antibiotic Molecule
2) Decreased Antibiotic Penetration and Efflux
3) Changes in Target Sites
4) Resistance Due to Global Cell Adaptations
What is the purpose of antibiotic stewardship?
- measure antibiotic prescribing (who has access)
- improve antibiotic prescribing by clinicals and use by patients (only when needed)
- minimize misdiagnoses or delayed diagnoses
- ensure that the right drug, dose, and duration are selected
Define bactericidal
kills sensitive organisms so that number of viable organisms fall rapidly after exposure
Define bacteriostatic
inhibits growth of bacteria but does not kill them
What are the 3 antimicrobial spectrums?
1) Narrow- spectrum: agent is active against a single species or limited group of pathogens
2) Broad-spectrum: agent is active against a wide range of pathogens
3) Extended-spectrum: agent falls in between (intermediate)
What are the components of a gram-positive bacterial cell wall?
lipoteichoic acid
peptidoglycan cell wall
plasma membrane
What are the components of a gram-negative bacterial cell wall?
outer lipid membrane
peptidoglycan
plasma membrane
All beta-lactam antibiotics interfere with ___
bacterial cell wall synthesis
Inhibition of bacterial transpeptidase (penicillin-binding protein) ___
inhibits peptidoglycan cross-linking
Penicillin V is a ____ antibiotic
narrow-spectrum
Penicillin V is administered in an ___
oral suspension
What are the adverse effects of penicillin V?
GI upset, nausea, vomiting, diarrhea, rash, hypersensitivity reactions (rare)
What illness is penicillin typically used for?
Group A streptococcal pharyngitis
Amoxicillin is an ____ penicillin that results in greater activity against additional ____
extended-spectrum
gram-negative bacteria
Cephalosporins are a large group of antibiotics that have greater ___
structural diversity
Cephalosporins are more resistant to ___ and increases their range of antimicrobial activity
beta-lactamases
Cefadroxil and cephalexin are first-generation ___
cephalosporins
Cefadroxil and cephalexin may be used as alternatives to ____
penicillin
What are the adverse effects of cefadroxil and cephalexin?
GI upset, nausea, vomiting, diarrhea, hypersensitivity (some cross-reactivity with penicillins)
Prokaryotic ribosomes are composed of ___ and ___ subunits
30S
50S
Macrolides inhibit ____ which functions to link amino acids together in a growing peptide chain
peptidyl transferase
Macrolides interfere with ___ and confer ___ activity
translocation
bacteriostatic
Azithromycin, Clarithromycin and Clindamycin are alternatives for those allergic to ___
penicillin
Azithromycin is less likely than other macrolide antibiotics to ___
interact with other drugs