P2 Spring Pcol2 01-23

Front 1

Whats an adv/disadv of Carbapenems, and their spectrum?

Back 1

Broadest spectrum B-lactam (gram +, gram -, and anaerobes)
Adv: Not susceptible to hydrolysis by B-lactamases
Disadv: Strong inducers of B-lactamase production (although they themselves are not affected by it)

Front 2

List some Carbapenems.

Back 2

Imipenem
Meropenem
Ertapenem
Doripenem

Front 3

List the gram + bacteria that Carbapenems are good against

Back 3

MSSA
Listeria monocytogenes
Enterococcus faecalis (PCN sensitive)
Nocardia asteroides
Strep
"Put the Magnifying LENS crosshairs over the gram + bacteria to kill them"

Front 4

List the gram negative bacteria that Carbapenems are good against

Back 4

P. aeruginosa (not ertapenem)
H. influenza
Acinetobacter (not ertapenem)
N. gonorrhea
Enterobacteriaceae (incl B-lactam resistant ones)
"When gram - bacteria see a carbapenem, they PHANE death"

Front 5

List some g+ or g- anaerobes that Carbapenems are good against

Back 5

Bacteroides
Fusobacterium nucleatum
Prevotella
Peptostreptococcus
Peptococcus magnus
Propionibacterium acne
"Fermenting Bacteria Prefer Propogating in a Poxic Pimple?

Front 6

List some bacteria that are resistant to Carbapenems

Back 6

Flavobacterium meningoseptium
ATYPICALs
MRSA
E. faecium
Stenotrophomonas maltophilia
"FAMEouS bacteria are resistant to carbapenems"

Front 7

List the main AE seen in Carbapenems, and compare its prevalence among the Carbapenems.

Back 7

Neurotoxicity (due to inhibition of GABA, decs CNS transmission, seizures?)
Imipenem > Ertapenem > Meropenem

Front 8

What bacteria are the Monobactams good (and bad) against?

Back 8

Good against: Gram -
Specifically:
P. aeruginosa
H. influenza
Acinetobacter
N. gonorrhea
*Enterobacteriaceae:
Proteus*
E. coli*
Morganella morganii*
Providencia*
Enterobacter*
Citrobacter freudii*
Klebsiella*
Note this list is the PHANEs that carbapenems are also good against

Bad: gram + and strict anaerobes

Front 9

List AEs for Monobactams

Back 9

Similiar to other B-lactams

Front 10

Whats the clinical use for Monobactams?

Back 10

If px is allergic to PCN or Cephalosporins give Monobactam (no cross reactivity)
Used in combo with gram + agent (since monobactams just cover gram -)

Front 11

What kind of killing profile is optimal for B-lactams in general?

Back 11

Conc independent killing
Time > MIC
Optimal conc at 4-6x MIC
No Post Antibiotic Effect (PAE) against gram - bacteria, so must keep conc above MIC during therapy

Front 12

What is Resistance Counter Selection? Whats the point of it?

Back 12

It describes the "inverted U phenomenon":
With suboptimal dosing the population of bacteria resistant to that drug increases (as nonresistant ones are killed off), but after optimal dosing is reached the resistant ones die too (downward slope of U curve on killing profile)
The point is that if you give patients a sub-optimal dose, resistant bacteria will increase and that drug may eventually become ineffective.
The first dose is very important to avoid creating resistance.

Front 13

Whats the shift in clinical administration of B-lactams?

Back 13

To give B-Lactams by continuous infusion (minimizes peaks/troughs, lowers cost, possibly more effective)

Front 14

What is the Innoculum Effect?

Back 14

Explains the discrepancy between invitro and invivo testing of B-lactam efficacy on bacteria, where invitro showed good efficacy but invivo did not.
The reason is that high levels of bacteria can "overwhelm" the drug so that its not very effective.
Innoculate means to introduce a microorganism into a person or animal.

Front 15

List the mechanisms that bacteria use against B-lactams

Back 15

Inactivation of B-lactam (via B-lactamase)
Altered permeability (B-lactam cant get to PBP)
Altered PBP (B-lactam cant attach to PBP)
Efflux pumps

Front 16

List some monobactams

Back 16

Just one: Aztreonam
wiki: It is resistant to some beta-lactamases, but is inactivated by extended-spectrum beta-lactamases.
Aztreonam has strong activity against susceptible gram-negative bacteria, including Pseudomonas aeruginosa. It has no useful activity against gram-positive bacteria or anaerobes. It is effective against Citrobacter, Enterobacter, E. coli, Haemophilus, Klebsiella, Proteus, and Serratia species.