Bug Treatments Flashcards
MSSA
-ASP (resists NSBLs and BSBLs)
-Pen + BLI
-1st>2nd>3/4th>5th cephs
–>cephamycins aren’t great for staph
No aztreonam
All carbapenems (Dori most effective)
Vancomycin only use if patient has beta lactam allergy
Dapto and tela
2.5, 3, or 4 generation FQs may work, but other drugs are better and resistance develops quickly during therapy (MOR on plasmid that bug carries causing end treatment resistance)
-AGs …use gentamycin + nafcillin or cefazolin (AG gram positive activity trend: staph > strep > enterococci)
Macrolides and Clindamycin (unless developed resistance…save Clinda to avoid resistance development; use Clinda for MRSA)
Linezolid
Streptogramin
TMP-SMX
Nitrofurantoin: UTI
MRSA
-Ceftaroline (5th)
Vancomycin, dapt, and televancin
Resistant to AGs by unknown mechanism (maybe use Vanco + AG?)
Susceptible to Clindamycin only if passes D test (CA-MRSA)
Linezolid (oral too!)
Streptogramin (good for complicated, resistant SSTI)
Tetracycline works for CA-MRSA > HA-MRSA
TMP-SMX gets HA-MRSA and CA-MRSA, oral and IV forms about 75% effective. Often see TMP/SMX + Clindamycin for MRSA…together get 100%
TMP/SMX useful and appropriate for MRSA since oral and IV formulations
MSSE
-ASP
-Pen + BLI
-1st>2nd>3/4th>5th
No aztreonam
All carbapenems
Vanco if beta lactam allergy
Dapto and televancin but don’t use
2.5, 3, and 4th generation FQs work but do not use them
AG…use gentamycin + vancomycin +/- rifampin
Macrolides and Clindamycin (unless developed resistance)
Linezolid
Streptogramin
TMP-SMX
MRSE
-Ceftaroline (5th)
Vancomycin, dapto, and televancin
Resistant to AG by unknown mechanism (AG + vanco works)
Resistant to macrolides and clindamycin except Telithromycin
Linezolid
Streptogramin
TMP-SMX, oral and IV forms about 75% effective
PSSP
-Any penicillin (Pen G most appropriate)
-1st>2nd>3/4/5th (non-acid AKI group only)
No aztreonam
No carbapenems
Vancomycin if beta lactam allergy
Dapto and televancin work but don’t use
2.5 and up FQs work, (resistant to early gen FQs because they don’t bind PAR)
Streptococci display low-level resistance to AG, so use in combo with a BL (AG + ceftriaxone)
Macrolides work (use ERY, CLR for CA-RTIs)
Clinda not really used due to rapid resistance and ADRs
Linezolid
Streptogramin
Bug susceptible to TMP-SMX but doesn’t eradicate the pathogen so don’t use!! Also facultative bug that can hide in anaerobic compartments; drug only works when bug is actively multiplying
PRSP
-Penicillins are “inneffective”–>use high doses to overcome PBPs
-Cephs need to have non-acid AKI group
2nd: cefpodoxime and cefuroxime
3rd-5th: ceftriaxone, ceftaxime, cefepime, ceftaroline
No aztreonam
All carbapenems (Dori> Imi> the rest)
Vanco, dapto, and televancin
2.5 and up FQs (respiratory FQs)
AG + Pen G…allows us to lower the dose of Pen G needed. Or use with ceftriaxone
No macrolide or clindamycin works except Telithromycin
Linezolid
Streptogramin
Resistant to TMP-SMX
All other streptococci
-Any penicillin
-1st>2nd>3-5th (as long as non-acidic AKI group)
No aztreonam
All carbapenems
Vanco (especially for viridans)
Dapto and televancin
2.5 and up FQs (except cipro)
Streptococci display low-level resistance to AG, so use in combo with a BL (Strep pyogenes resistant to AGs alone)
For viridians: use gentamycin + Pen G
Macrolides work, Clinda not used due to rapid resistance
Marcolides can be cidal for streptococci at high concentrations
Streptogramin
Bug susceptible to TMP-SMX but doesn’t eradicate the pathogen so don’t use!! If you don’t eradicate strep it can transmit to baby through birth canal
Enterococcus faecalis
-APs work the best, but Pen G can work too (synergy with AG)
-ASPs will not work (PBP doesn’t bind)
-Piperacillin works, but not great
-Ticarcillin not effective
-No cephs (due to modified PBPs)
No aztreonam
All carbapenems except ertapenem
Vanco is AOC in serious infections
Dapto?
Telavancin
No FQs (but more susceptible than faecium)
Functionally resistant to AGs alone; must use in combo with BL (ampicillin or pen G) or vanco for BL allergic
No macrolide or clindamycin works…limited entry and modified ribosomes
Linezolid (works for VRE too!)
Streptogramin DOESN’T WORK!!! BUG developed all 3 MOR!
Tetracycline doesn’t work
Appear susceptible to TMP-SMX but NEVER use; bugs are scavengers!!
Nitrofurantoin: UTI
Enterococcus faecium
-less susceptible than faecalis
-AP>Pen G (synergy with AG)
-Piperacillin works but not great
All glycopeptides
Can only use Gentamicin in combo with a BL (Tobra and Ami don’t work, even with a BL!)
No macrolide or clindamycin works
Streptogramin works!!!
Tetracycline doesn’t work
Appear susceptible to TMP-SMX but NEVER use; bugs are scavengers!!
Listeria monocytogenes
-AP>Pen G (synergy with AGs)
-Pen V does not work
-ESPs work (a little)
Vanco IV for gram + meningitis
Dapto and televancin
3rd or 4th gen FQ
Display low-level resistance to AG, so use in combo with a BL (AG + ampicillin)
Marcolides and clindamycin work!
Linezolid
TMP-SMX AOC for Gram + bacilli (Listeria meningitis!)
Corynebacterium
All glycopeptides
Usually susceptible to AGs (use with Pen G) Pen G + AG = AOC
Linezolid!!
TMP-SMX AOC for Gram + bacilli
Bacillus
- Vancomycin for Bacillus cereus
- All other bacillus are susceptible to Pens/Beta-lactams
Acinetobacter
-AP/ESP + BLI may be effective but never use it alone
-3rd/4th gen cephs maybe, but not reliable
-not ceftaroline (5th)
-no Aztreonam
All carbapenems can kill 75% of these except ertapenem
Susceptible to FQs (always want to recommend multiple drugs for this bug such as carbapenem+ FQ)
AG might kill 70%…best to combine with FQ and carbapenem
NOT Streptogramin
Resistant to TMP; SMX effective but only 10-30%; don’t use
Moraxella catarrhalis
-AP + BLI or ESP + BLI
-2nd-5th gen cephs (when possible, use 2nd gen with AKI): cephamycins will work but want to save these for other infections
Aztreonam works
All carbapenems
All FQs
AG works but never use! Other drugs are better!
Macrolide works, clindamycin doesn’t
Streptogramin works but never use
Resistant to TMP, SMX effective but only 10-30%; don’t use
Neisseria gonorrhea
-NP + BLI maybe will work…but probably has really high MIC so don’t use
-AP + BLI or ESP + BLI will work
-2nd-5th gen cephs–>ceftriaxone (3rd) is AOC because of long t1/2
-3rd>2nd but can use either
-others listed: cefuroxime, cefpodoxime, cefixime
Aztreonam works
All carbapenems
FQ resistant so don’t use
AG (Streptomycin > Gentamicin)….not used in combo
Azithromycin gets this the best because of two basic amine groups, it distributes best of macrolides (ERY, CLAR work too)
Use azithromycin (low MIC and long half life!)
Clindamycin ineffective
Spectinomycin alone for AG if N. gonorrhoeae doesn’t respond to BL
Tetracyclines like to be resistant
Resistant to TMP, SMX effective but only 10-30%; don’t use
Neisseria meningitidis
-NP (Pen G) or AP–>all penicillins work but Pen G is AOC
–>caution with high Pen G doses and seizures
-3rd>2nd gen–>ceftriaxone is AOC
Aztreonam works
All carbapenems (do not use imipenem because it can cause seizures)
No FQ because can cause seizures
AG works (for super serious patient use Pen G + AG see casebook)
No macrolides or clindamycin
Streptogramin works but never use
Haemophilus influenza
-AP + BLI or ESP + BLI
-2nd-5th gen cephs will work: want to use 2nd gen when you can (except in meningitis, use 3rd)
Aztreonam
All carbapenems
All FQs
AG works but never use! Other drugs are better!
Macrolide works (CLR, TEL, AZI)
Erythromycin MIC is high
clindamycin doesn’t work
Clarithromycin used for RTIs!
Streptogramin works but never use
Variable susceptibility to TMP-SMX but there are better drugs
Pasturella/Eikenella
-All penicillins except ASPs (ASPs don’t get any G-)
-Pasturella=NP
-Eikenella=AP
***prefer to use amox/clav to cover staph as well
-Penicillins work better than cephalosporins, but all cephalosporins are active (5th>2nd>all rest)
Aztreonam
All carbapenems
All FQs
AG works but never use! Other drugs are better!
Macrolide works
Tetracycline (but use a BL!)
E. coli
-AP + BLI or ESP + BLI
*clavulanate is the only BLI that inhibits ESBLs
-NP and ASPs wont work
-2nd-5th gen cephs can work…but really 3rd-5th are best (2nd not likely to be effective)
Aztreonam
All carbapenems (mero and dori are the best)
All FQs (although seeing more resistance)
AG works
Macrolide doesn’t work
Tetracyclines can get in (have intrinsic activity) but many Enterobacteriacea have become resistant.
In general, FQ > Tetra > Macs for GNB
TMP-SMX susceptible, but increasing resistance. Know the bug strain in your area.
Nitrofurantoin: UTIS