E2 Erdman aminoglycosides Flashcards
what 2 things are reasons why the AMG class is dosed individually for each pt and require serum conc monitoring
- interpatient variability in Vd and Cl
- narrow therapeutic window/index
5 AMGs to know for this lecture
gentamicin
tobramycin
amikacin
streptomycin
plazomicin (new)
T or F:
AMGs are very polar compounds that are polycationic
true
AMG MOA
bind to 30S!!!!
- must bind to and diffuse through outer membrane (passive) and cytoplasmic membrane (energy-dependent) to reach ribosome
AMGs are (time/conc) dependent and (cidal/static)
conc, cidal
T or F:
AMGs are capable of crossing lipid-containing cellular membranse
false
T or F:
AMGs have excellent oral absorption
false
T or F:
AMGs penetrate through meninges well
F, they dont
T or F:
binding to 30s subunit is reversible
false
3 mechs of resistance for AMGs
- altered uptake
- AMG-modifying enzymes
- alteration in ribosomal binding sites (primarily with strepto)
AMGs are NEVER USED ALONE for GP aerobes, what are they used with?
low doses of cell-wall active agents to provide synergy - primarily with gent
AMG SoA:
GP aerobes
Viridans strep (gent)
enterococcus spp (static, gent or strepto)
Most S. aureus ** (MRSA/MSSA)
not very active against GN aerobes.
A. Amikacin
B. Plazomicin
C. Gentamicin
D. Tobramycin
E. Streptomycin
E
MOST active against GN aerobes
A. Amikacin
B. Plazomicin
C. Gentamicin
D. Tobramycin
E. Streptomycin
A
key GN bacteria AMGs have activity against
Pseudomonas aeruginosa
AMG SoA:
anaerobes
not active
AMGs display a PAE for most ___ bacteria and S. aerues
GN
has activity against ESBLs, AmpCs, KPC/OXA
A. Amikacin
B. Plazomicin
C. Gentamicin
D. Tobramycin
E. Streptomycin
B
AMG synergy with cell wall active agents against what key 3 bacterias
Enterococcus
S aureus
P. aeruginosa
True/False:
Aminoglycosides can be
used as monotherapy for the
treatment of infections due to
Gram-positive aerobes.
F
AMGs:
drug absorption after IM injection may be decreased in patients with hypotension and should not be used in ________ ____ pts
critically ill
AMGs are distributed primarily in the ?
extracellular fluid compartment
AMGs distribute (well/poorly) into CSF
poorly
what body weight should be used for AMGs
IBW (or ADW in obese pts)
what must be taken into account to calculate appropriate dose of AMGs
volume status - conc dependent killers so
AMGs elimination
85-95% eliminated unchanged in kidney
Elimination t1/2 depends on?
renal function
T or F:
AMGs are removed by hemo
true
which of the following DO NOT require serum conc monitoring?
A. Amikacin
B. Plazomicin
C. Gentamicin
D. Tobramycin
E. Streptomycin
B and E
It is imperative to achieve therapeutic AMG concs. within 24 hours in pts with GN _____
sepsis, increased mortality with sub-therapeutic conc
are eligible for once-daily dosing
A. Amikacin
B. Plazomicin
C. Gentamicin
D. Tobramycin
E. Streptomycin
A C D
“GTA”
True/False:
All patients can receive the
same aminoglycoside dose
since there is little
interpatient variability in Vd
and Cl.
false no fuckin shit
gentamicin/tobramycin.
Intra- abdominal infections, urosepsis, skin and soft tissue infections:
peak:
trough:
peak: 13-20
trough: <0.5
amikacin. Intra-abdominal infections, urosepsis, skin and soft tissue infections:
peak:
trough:
peak: 40-50
trough: <8
AMG clinical uses:
A/G/T
GN aerobes (usually w/ b-lactams)
AMG clinical uses:
plazo
complicated UTI due to MDR GN aerobes
AMG clinical uses:
G/S
GP aerobes (with synergy)
tuberculosis:
A. Amikacin
B. Plazomicin
C. Gentamicin
D. Tobramycin
E. Streptomycin
E
AMG AEs:
nephrotoxicity
nonoliguric azotemia due to proximal tubular damage
AMG AEs:
nephrotoxicity risk factors
- prolonged high troughs
Irreversible AMG AE (unique to class)
ototoxicity
Which of the following antibiotics
does NOT have activity against
Pseudomonas aeruginosa?
A. Cefepime
B. Ciprofloxacin
C. Tobramycin
D. Piperacillin
E. Ceftriaxone
E
Which of the following antibiotics
does NOT cause nephrotoxicity?
A. Gentamicin
B. Telavancin
C. Vancomycin
D. Azithromycin
E. Nafcillin
D
