Gram Positive Agents

Question 1

glycopeptides

Answer 1

vancomycin

Question 2

streptogramins

Answer 2

quinupristin:dalfopristin

Question 3

oxazolidinones

Answer 3

linezolid
tedezolid

Question 4

lipopeptides

Answer 4

daptomycin

Question 5

lipoglycopeptides

Answer 5

telavancin
oritavancin
dalbovancin

Question 6

vancomycin MOA

Answer 6

inhibits 2nd stage of cell wall synthesis by binding to the D-Ala-D-Ala cell wall precursors

Question 7

vancomycin cidal or static, time or conc dependent

Answer 7

bactericidal, slow

Question 8

mechanism of resistance vancomycin

Answer 8

modification of the D-Ala-D-Ala vancomycin binding site

Question 9

spectrum of activity vancomycin

Answer 9

gram positives
anaerobes

Question 10

target organisms vancomycin

Answer 10

PRSP
MSSA
MRSA
C. diff (po only)

Question 11

which is drug of choice for MRSA

Answer 11

vancomycin

Question 12

when should we measure serum

Answer 12

1 hour after end of infusion

Question 13

does vanc penetrate CSF

Answer 13

no

Question 14

how is vanc eliminated? dose adjust?

Answer 14

excreted by kidney, requires dose adjustments based on CrCl

Question 15

which gram positive agent can be used for c. diff?

Answer 15

vancomycin orally

Question 16

adverse events of vancomycin

Answer 16

red man syndrome
neohrotoxicity, ototoxicity
interstitial phlebitis

Question 17

risk factors for nephro and ototoxicity

Answer 17

high doses
prolonged therapy
use of other agents causing nephro or ototox like chemo or pressors

Question 18

how does red man syndrome happen

Answer 18

related to rate of infusion, happens if given fast

Question 19

if red man syndrome happens, can you give vancomycin again

Answer 19

can give it again but prolong the infusion or give pretreatment with antihistamines or corticosteroids

Question 20

mechanism of action quinupristin/dalfopristin

Answer 20

inhibits protein synthesis by binding to 50S ribosomal subunits

Question 21

quinupristin:dalfopristan cidal or static, conc or time dependent

Answer 21

static, time dependent

Question 22

linezolid, tedizolid MOA

Answer 22

inhibits protein synthesis by binding to the 50S ribosomal subunit near 30S interface

Question 23

linezolid, tedizolid static or cidal, time or conc

Answer 23

static
time dependent (linezolid)
conc dependent (tedizolid)

Question 24

mechanism of action daptomycin

Answer 24

causes membrane depolarization by inserting lipophillic tail in cell wall to form transmembrane channel, inhibits DNA synthesis

Question 25

daptomycin, cidal or static, time or conc dependent

Answer 25

cidal concentration dependent

Question 26

telavancin, oritavancin, dalbavancin MOA

Answer 26

inhibits cell wall synthesis by binding to D-Ala-D-Ala cell wall precursors AND causes cell membrane depolarization by inserting lipophilic tail in cell wall

Question 27

telavancin, oritavancin, dalbavacin cidal or static, time or con

Answer 27

cidal concentration dependent

Question 28

Synercid mechanism of resistance

Answer 28

alteration in ribosomal binding site, enzymatic inactivation

Question 29

linezolid, tedizolid mechanism of resistance

Answer 29

alteration in ribosomal binding site (rare)

Question 30

daptomycin mechanism of resistance

Answer 30

rarely reported, altered cell wall membrane binding through loss of membrane protein

Question 31

telavancin, oritavancin, dalbovancin mechanism of resistance

Answer 31

modification of the D-Ala-D-Ala vancomycin binding site

Question 32

spectrum of activity Synercid (quinupristin, dalfopristin)

Answer 32

gram positives only anaerobes

Question 33

spectrum of activity linezolid, tedizolid

Answer 33

gram positive only anaerobes

Question 34

spectrum of activity daptomycin

Answer 34

gram positives only anaerobes

Question 35

spectrum of activity telavancin, oritavancin, dalbovancin

Answer 35

gram positives only anaerobes

Question 36

target organisms for gram positive agents

Answer 36

PRSP MRSA MSSA VRE (except quinupristin: dalfopristin)

Question 37

gram positive agents covering VISA and VRSA

Answer 37

linezolid, tidezolid daptomycin telavancin, oritavancin, dalbovancin

Question 38

which gram positve agents have CSF penetration?

Answer 38

linezolid

Question 39

which gram positives require renal dose adjustments

Answer 39

daptomycin telavancin dalbavancin

Question 40

which gram positive requires hepatic dose adjustments

Answer 40

Synercid

Question 41

side effects of Synercid (quinupristin, dalfopristin)

Answer 41

phlebitis myalgias arthralgias

Question 42

linezolid side effects

Answer 42

optic and peripheral neuropathy thrombocytopenia, anemia

Question 43

daptomycin side effects

Answer 43

myopathy and CPK elevation acute eosinophillic pneumonia

Question 44

telavancin, oritavancin, dalbovancin side effects

Answer 44

nephrotoxicity QT prolongation taste werd infusion site reactions

Question 45

which drug has risk of serotonin syndrome?

Answer 45

linezolid

Question 46

which drug has interaction with HmgCoa reductase?

Answer 46

daptomycin, hold the statin

Question 47

which drug has CYP3a4 interaction

Answer 47

Synercid

Question 48

what drugs should you avoid with Synercid

Answer 48

3A4s cyclosporine statins tacrolimus carbamezepine

Question 49

which drug interacts with aPTT tests

Answer 49

oritavancin, dalbovancin, telavancin

Question 50

which gram positive should we avoid in pregnancy

Answer 50

dalbavancin, oritavancin, telavancin

Question 51

which drugs preferred for VRE

Answer 51

linezolid daptomycin