EXAM 2 cephalosporins, carbapenems, monobactams Flashcards
Cephalosporins MOA
interfere w/ PBPs on bacterial cell walls
bactericidal
cephalosporins MOR
Production of b-lactamase enzymes
Alterations in PBPs leading to decreased binding affinity (MRSA, PSRP)
Several have activity against PRSP; one is active against MRSA(ceftaroline)
Alteration of outer membrane leading to decreased penetration
cephalosporin spectrum
Lose gram (+) activity w/ increase gram (-) activity as you go 1st -> 2nd -> 3rd -> 4th
Greater b-lactamase stability as you go from 1st -> 2nd -> 3rd -> 4th
1st gen cephalosporins
cefazolin (parenteral)
cephalexin (oral)
1st gen cephalosporin spectrum
MSSA (cefazolin drug of choice)
2nd gen cephalosporins
cefuroxime
cefprozil
cefoxitin
2nd gen cephalosporin spectrum
MSSA
BDA (cefoxitin)
3rd generation cephalosporins
ceftriaxone
ceftazidime
cefpodoxime
3rd gen cephalosporin spectrum
PRSP (ceftriaxone)
pseudomonas (ceftazidime)
4th generation cephalosporin
cefepime
cefepime spectrum
PRSP
MSSA
Pseudomonas
anti-MRSA cephalosporin
Ceftaroline
ceftaroline spectrum
PRSP
skin and soft tissue MRSA
MSSA
cefiderocol spectrum
Fetroja
ESBLs, AMPCs
cephalosporin b-lacatamase inhibitor combos
Ceftolozane-tazobactam (zerbaxa)
Ceftazidime-avibactam (avycaz)
Ceftolozane-tazobactam (zerbaxa)
Ceftazidime-avibactam (avycaz)
spectrum
pseudomonas aeruginosa
Which cephalosporin is considered potential drug of choice for MSSA infections?
Ceftazidime
Cefotetan
Cefazolin
Ceftolozane-Tazobactam
Cefnoicid
Cefazolin
Which cephalosporin does NOT have activity against Pseudomonas aeruginosa?
Ceftriaxone
Ceftazidime
Cefepime
Ceftolozane-Tazobactam
Ceftazidime-Avibactam
Ceftriaxone
Cephalosporin pharmacology
Time>MIC is PD parameter
cephalosporin distribution
Widely distributed
CSF concentrations ONLY achieved with PARENTAL cefuroxime, 3rd gen and 4th gen agents
Cephalosporin elimination
Most are primarily eliminated unchanged by kidney
Ceftriaxone (biliary) + Cefoperazone (liver) are NOT eliminated by kidneys
what is the half life of cephalosporins?
most have <2 hrs t 1/2
ceftriaxone has 8 hr t1/2 –> can give it QD
adverse effects of cephalosporins
Hypersensitivity
MTT side chain –> hypoprothrombinemia and ethanol intolerance
IV calcium and ceftriaxone precipitates –> nonconvulsice status epilepticus
T/F: a patient who developed anaphylaxis to penicillin requiring ICU admission can safety receive any cephalosporin
FALSE
what are the available carbapenems?
imipenem
meropenem
ertapenem
doripenem
New agents: meropenem/vaborbactam and imipenem/relebactam
carbapenems MOA
inhibit cell wall synthesis by binding to PBP
primary target is PBP-2
bactericidal
carbapenems MOR
b-lactamase production
- highly stable against b-lactamse so drug of choice for AMPc and ESBLs
decrease permeability
alteration in PBPs
carbapenems spectrum
most broad spectrum agents (liquid jesus or gorilla cillin)
MSSA
pseudomonas (except erta)
BDA (bacteroides)
T/F carbapenems are highly stable against b-lactamase enzymes are considered DoC for serious infections due to ESBL and AmpC bugs
TRUE
T/F Meropenem/vaborbactam and imipenem/relabactam were developed to provide activity against KPC producing enterobacterales
TRUE
carbapenems pharmacology
Time>MIC like all b-lactams
clinically useful synergy with AMG
carbapenems distribution
widely distributed in body tissues and fluids
CSF penetration –> meropenem is the only one that gets enough penetration
carbapenems elimination
all are primarily eliminated unchanged kidneys –> need dose adjustments
short elimination, but ertapenem has t1/2 4 hrs so can give QD dosing
imipenem metabolism
undergoes hydrolysis by DHP which forms nephrotoxic metabolite
given with cilastatin a DHP inhibitor
carbapenem adverse effects
hypersensitivity higher
CNS: confusion, dizzy, hallucination, seizures
risk factors: seizures, CNS disorders, high dose, renal insufficiency
which carbapenem is co-formulated with cilastatin to prevent DHP degradation in the renal brush border and subsequent nephrotoxicity?
Doripenem
Meropenem
Ertapenem
Imipenem
All carbapenems are co-formulated with cilastatin
Imipenem
Monobactam spectrum
psuedomonas aeruginosa
aztrenoam distribution
wide distribution in body tissues and fluids
penetrates CSF in pressence of inflamed meniges
Which of the following antibiotics can be used in a patient who developed angioedema, hives, and hypotension requiring ICU admission after an IM injection of penicillin?
Ampicillin
Meropenem
Ceftaroline
Aztreonam
None of the above
Aztreonam
