ID I: Background and ABX by Class Flashcards
penicillins, cephalos, carbapenems, AGs, FQs, macrolides, TTCs, SMX/TMP, Nitrofurantoin, Specific Pathogen Tx, Renal Dosing
common CNS/meningitis pathogens
s pneumo
n meningitidis
h influenzae
GBS (kids)
listeria (adults)
common URI pathogens
strep pyogenes
s pneumo
h influenzae
m cat
common lower resp tract infection pathogens
community: s pneumo, h inf, atypicals, enteric GNR
hospital: s aureus (MSSA, MRSA), pseud, acinetobacter baumannii, enteric GNR (including ESBL and MDR), s. pneumo
common endocarditis pathogens
s aureus/MRSA
s epidermidis
streptococci
enterococci
common SSTI pathogens
s aureus
s pyogenes
staph epidermidis
G+/- anaerobes, aerobes
GNR (in T2DM)
common UTI pathogens
e coli
proteus
klebsiella
staph saphrophyticus
enterococci
common bone/joint infection pathogens
s aureus
s epidermidis
streptococci
N. gonorrhoeae
GNR
what are the enteric gram - rods
proteus
e coli
klebsiella
enterobacter
serratia
G+ vs G-
G+ have a thick cell wall and stan dark purple on gram stain from crystal violet
G- have a thin cell wall and stain pink on gram stain from safranin counter stain
atypical pathogens and drugs that cover then
legionella
chlamydia
mycoplasma pnemoniae
mycobacterium
covered by TTC, macrolides, FQs and tigecycline, vibramycin
cultures show G+ cocci in clusters
what pathogen could this be
s aureus (MSSA or MRSA)
cultures show G- cocci
what pathogen could this be
neisseria spp.
cultures show G+ cocci in pairs
what pathogen could this be
strep pneumo
strep spp.
enterococcus (including VRE)
cultures show G+ spores
what pathogen could this be
anaerobes
peptostreptococcus
c diff
clostridium spp.
cultures show G- coccobacilli
what pathogen could this be
acineobacter baumannii
bordatella pertussis
moraxella cat.
cultures show G- rods (GNR)
what pathogen could this be
colonize gut = proteus mirabilis, e coli, klebsiella, serratia, enterobacter, citrobacter
curved or spiral GNR = h pylori, campylobacter spp, treponema spp.
do not colonize gut = pseud, h influenzae, providencia
what GNR do not colonize the gut
pseud, h influenzae, providencia
If a pathogen in + for ESBL, what does this mean and what are not treatment options? What are tx options?
pathogen has extended spectrum beta lactamases which makes all penicillins and most cephalosporins ineffective
tx options: carbapenems, ceftazidime/avibactam, ceftolozane/tazobactam
what are the commonly resistant bugs
SPEEAK
s aureus (MRSA)
pseug aeruginosa
e coli (ESBL, CRE)
e. faecalis, e. faccium (VRE)
acinetobacter baumannii
klebsiella (ESBL, CRE)
which abx has a BBW for c diff
clindamycin
which abx are hydrophilic and which are lipophilic? How does this affect the drug?
hydrophilic: B lactams, AGs, vanco, dapto, polymixins
inc hydrophilicity –> dec Vd –> renal elim and tox–> dec cell penetration and low F–> IV:PO not 1:1 and low activity against atypicals
lipophilic: TTC, macrolides, FQs, rifampin, linezolid
inc lipophilicity –> inc Vd –> inc cell penetration –> activity against atypicals and more 1:1 IV:PO ratios and hepatic elim
what does concentration dependent dosing mean? Which drugs use this?
goal is to have a high Cmax to inc killing while having a low trough to dec toxicity (large dose, long interval)
AGs, FQs, dapto
what does exposure-dependent dosing mean? Which drugs use this?
AUC:MIC is used to assess exposure over time in TDM
vanco, macrolides, TTC, polymixins
what does time>MIC dependent dosing mean? Which drugs use this?
goal is to maintain drug level>MIC for most of interval; uses
shorter dosing interval or extended/continuous dosing
B-lactams (penicillins, cephalosporins, carbapenems)
what are the natural penicillins and what do they cover
pen VK, Pen G
streptococcus
enterococcus
mouth flora
what are the anti-staph penicillins and what do they cover
naficillin, oxacillin, dicloxacillin
streptococcus
MSSA
which penicillins do not need renal dose adjustments
anti-staphs!
oxacillin, dicloxacillin and naficillin
what are the aminopenicillins and what do they cover
amox +- clav, amp +- sul
streptococcus
enterococcus
G- anaerobes in mouth flora
adding clavulanate or sulbactam extends coverage to
HNPEK
b frag (anaerobe)
MSSA
what is the extended spectrum penicillin? What does it cover?
pip/tazo
covers same bugs as aminopenicillin/beta lactamase-i (streptococcus, enterococcus, G- mouth flora, HNPEK, MSSA, anaerobe b frag)
PLUS
pseudomonas and CAPES
what are the G- bacilli
CAPES
camphylobacter
acinetobacter
providencia
enterobacter
serratia
Pen VK is first line for __________
dosing?
pharyngitis (strep throat) and mild non-purulent SSTI without abscess
125-500mg Q6-12H on empty stomach
Penicillin G must be administered
A. IV
B. IM
C. PO
D. IV or IM
B. IM
Pen G has BBW for IV administration, only administer IM!
ampicillin and amp/sul are only compatible with ____
NS
amp/sul IV dosing
1.5-3g Q6h
what is the use of probenacid with penicillins
decreases penicillin renal excretion which is used as a mechanism in severe infections
pip/tazo dosing (IV) and infusion time
3.375mg IV Q6H or 4.5g IV Q6-8H
over 4 hours
penicillins increase/decrease bleed risk with warfarin?
methotrexate [ ] is increased/decreased by penicillins?
naficillin and dicloxicllin increase/decrease clot risk with warfarin?
penicillins dec clot factor production and pose a bleed risk
MTX [ ] increase with penicillins
naficillin and dicloxacillin dec warfarin efficacy and pose a clot risk
what are the contraindications to penicillins?
allergy
augmentin and unasyn with cholestatic jaundice or hepatic dysfunction with prev use
ER forms and augmentin 875mg if CrCl <30
amoxicillin/clav is a _____ ratio to decrease risk of ___________
A. 14:1 ; constipation
B. 14:1 ; diarrhea
C. 5:1 ; constipation
D. 5:1 ; diarrhea
B. 14:1 ; diarrhea
SMX/TMP is 5:1
which penicillin is a vesicant and is preferably administered in a central line?
naficillin
What should be monitored when a patient is on a penicillin
allergic reaction, LFTs, renal function, rash (SJS/TEN), hemolytic anemia (+coombs test), myelosuppression with prolonged use
what is the pneumonic for non-CAPES G- organisms
HNPEK
h. influenzae
neisseria
proteus
e coli
klebsiella
as cephalosporin generation increases, _____ coverage increases
gram negative
as cephalosporin generation increases, penicillin (PCN) cross reactivity ________________–
decreases
first generation cephalos
coverage
cephalexin
cefazolin
weak G-/PEK coverage
strep
staph
second generation cephalos
coverage
cefuroxime
- covers staph and resistant HNPEK
cefotetan and cefoxitin
- cover staph, resistant HNPEK and b frag!
what type of bacteria is b frag
G- anaerobe
3rd gen cephalos
coverage
ceftriaxone, cefotaxime, cefdinir
- cover resistant strep virdans, MSSA, G+, HNPEK
ceftazidime
- NO G- COVERAGE, but covers pseud
4th gen cephalo
coverage
cefepime
- resistant strep virdans, MSSA
- HNPEK, CAPES, pseud
5th gen cephalo
coverage
ceftaroline
- G- anaerobes, MSSA
- MRSA
cefazolin
which generation
dosing
first
IV/IM 1-2g q8h
only cephalosporin without renal dose adjustments
CTX
cephalexin
which generation
dosing
first
250-500mg q6-12h
cefuroxime
which generation
dosing
second, group 1
PO/IV/IM 250-1500mg q8-12h
oral cephalosporins
cephalexin (1st)
cefuroxime (2nd)
cefdinir (3rd)
cefotetan
which generation
dosing
second - group 2
IV/IM 1-2g q12h
what is unique about cefotetan
has a unique side chain that increases bleed risk and risk of disulfiram reaction
cefoxitin
which generation
dosing
second - group 2
IV/IM 1-2g q6-8h
cefdinir
which generation
dosing
3rd - group 1
300mg q12h or 600mg qd
CTX
which generation
dosing
3rd - group 1
IV/IM 1-2g q12-24h
cefotaxime
which generation
dosing
3rd - group 1
IV/IM 1-2g q4-12h
ceftazidime
brand name
which generation
dosing
Tazicef
3rd - group 2
IV/IM 1-2g q8-12h
cefepime
which generation
dosing
4th
1-2g q8-12h
ceftaroline
which generation
dosing
5th
600mg q12h
CTX is contraindicated in
neonates (hyperbilirubinemia)
use with Ca-containing IV products
adverse effects of all cephalos
inc LFTs, seizure, AIN, hemolytic anemia, myelosuppression with long term use, SJS/TEN
If a patient is on an antacid, which cephalos are to be avoided
cefuroxime
cefpodoxime
cefdinir
cephalo monitoring
LFTs, renal function, CBC