micro - antimicrobials Flashcards
1
Q
inhibiting peptidoglycan cross-linking –> block cell wall synthesis
A
penicillin, methicillin, ampicillin, piperacillin
cephalosporins, zaztreonam, imipenem
2
Q
block peptidoglycan synthesis
A
bacitran and vancomycin
3
Q
inhibit folic acid synthesis (methylation) –> block nucleotide synthesis
A
sulfonamides, trimethroprim
4
Q
block DNA topoisomerase
A
fluoroquinolones
5
Q
block mRNA synthesis
A
rifampin
6
Q
damage DNA
A
metronidazole
7
Q
block protein synth at 50S ribosomal unit
A
chloramphenicol, clindamycin, linezolid, macrolides, streptogramins (-pristin)
8
Q
block protein synth at 30S ribosomal unit
A
aminoglycosides, tetracycline
9
Q
macrolides MOA
A
block 50S
10
Q
penicillin general
A
prototype beta lactam, blocks peptidoglycan cross linking - inhibits cell wall synthesis
11
Q
penicillin MOA
A
binds penicillin-binding protein (transpeptidases) –> block transpeptidase cross-linking of peptidoglycan
activate autolytic enzymes
12
Q
penicillin clinical use
A
gram positive organisms - strep pneumo, strep pyogenes, actinomyces
neisseria meningitis, treponema pallidum, syphilis
13
Q
penicillin toxicity
A
hypersensitivity rxn
hemolytic anemia
14
Q
penicillin resistance
A
beta-lactamase cleaves beta-lactam ring
15
Q
penicillin G
A
IV and IM form
16
Q
penicillin V
A
oral
17
Q
penicillin bactericidal vs.
A
gram positive cocci and rods, gram negative cocci, and spirochetes
18
Q
penicillinase-resistant penicillins
A
NOD IF U RESIST
nafcillin, oxacillin, dicloxacillin
19
Q
PRP MOA
A
same as penicillin - bind PBP (transpeptidase) -> inhibit transpeptidase crosslinking of peptidoglycan –> inhibit cell wall synthesis
narrow spectrum!
20
Q
PRP MOA of resistance to penicillinase
A
bulky R group blocks access of beta-lactamase to beta-lactam group
21
Q
which PRP used for staph
A
nafcillin
22
Q
PRP clinical use
A
staph aureus (except MRSA)
23
Q
MRSA resistance MOA
A
altered penicillin binding protein target site
24
Q
PRP toxicity
A
hypersensitivty rxn
interstitial nephritis
25
aminopenicillins
ampicillin and amoxicillin
26
aminopenicillins MOA
same as penicillin *bind penicillin binding protein (transpeptidases) --> inhibit transpeptidase crosslinking of peptidoglyan --> inhibit cell wall synthesis
wider spectrum!
27
aminopenicillin with greater oral bioavailability
amoxicillin
28
aminopenicillin clinical use
extended spectrum penicillin (AMPED UP) - HELPSS kill enterococci
h flu, e coli, listeria monocytogenes, proteus mirabilis, salmonella, shigella, enterococci
29
aminopenicillin toxicity
hypersensitivity rxn, ampicillin rash, pseudomembranous colitis
30
aminopenicillin resistance
beta lactamase cleaves beta lactam ring ***add CLAVULANIC acid to help protect
31
antipseudomonals
ticarcillin, pipercillin
32
antipseudomonals MOA
same as penicillin - extended spectrum
33
antipseudomonals clinical use
pseudomonas and gram negative rods
| suscept to beta-lactamase --> use with beta-lactmasease inhibitors
34
antipseudomonals toxicity
hypersensitivity rxn
35
beta lactamse inhibitors
CAST - clavulanic acid, sulbactam, tazobactam
| often added to penicillin antibiotics to protect antibiotic from destruction by beta-lactamase
36
cephalosporins MOA
beta lactam - block peptidoglycan cross linking --> inhibit cell wall synthesis **lessss susceptible to beta-lactamase
bactericidal
37
not covered by cephalosporins
LAME = listeria, atypicals (chlamydia/mycoplasma), MRSA and enterococci
38
which cephalosporin blocks MRSA
ceftaroline
39
cephalosporins 1st generation
cefazolin, cephalexin
40
cephalosporins 1st generation bugs
PEcK - gram positive cocci, proteus mirabilis, e coli, klebsiella pneumoniae
41
what is used prior to surgery to prevent staph aureus wound infections
cefazolin
42
cephalosporins 2nd generation
cefoxitin, cefaclor, cefuroxime
43
cephalosporins 2nd generation bugs
HEN PEcKS
gram positive occci, h flu, enterobacter aerogenes, neisseria, proteus mirabilis, e coli, klebsiella pneumo, serratia marcescens
44
cephalosporins 3rd generation
ceftriaxone, cefotaxime, ceftazidime
45
cephalosporins 3rd generation bugs
serious gram negative infections resistant to other beta-lactams
46
cephalosporins 4th generation
cefepime
47
cephalosporins 4th generation bugs
pseudomonas and gram positive
48
ceftriaxone
meningitis and gonorrhea
49
ceftazidime
pseudomonas
50
cephalosporins toxicity
HS rxn, vitamin K deficiency
low cross-reactivity with penicillins
increase nephrotoxicity of amino glycosides
51
aztreonam MOA
prevents peptidoglycan cross linking by binding PBP3
synergistic with amino glycosides
no cross-allergenicity with penicillins
52
monobactam resistant to beta-lactamases
aztreonam
53
aztreonam clinical use
gram negative rods ONLY
| for penicillin allergic patients and those with renal insufficiency who cant tolerate amin glycosides
54
aztreonam toxicity
nontoxic - occasional GI upset
55
imipenam
broad spectrum beta-lactamase resistant carbapenem
56
imipenam MOA
inhibit peptidoglycan cross linking --> inhibit cell wall synth
always administered with cilastatin to decrease inactivation of drug in renal tubules
kill is lastinnn with cilastatin
57
cilastatin MOA
inhibits renal dehydropeptidase I
58
imipenam clinical use
gram positive cocci, gram neg rods and anaerobes
| SE limit use to life-threatening infections or after other drugs failed
59
meropenem
reduced risk of seizures and stable to dehydropeptidase I
60
carbapenem toxicity
GI distress, skin rash, and CNS toxicity (seizure) and high plasma levels
61
newer carbapenems
ertapenem and doripenem
62
vancomycin MOA
binds D-ala D-ala portion of cell wall precursors --> inhibits cell wall peptidoglycan formation
*bactericidal
63
vancomycin clinical use
gram positive
| serious multidrug resistant organisms like MRSA< enterococci and c diff
64
pseudomembranous colitis c diff
oral vancomycin
65
MRSA
vancomycin
66
vancomycin toxicity
NOT - nephrotoxicity, ototoxicity, thrombophlebitis
| well tolerated in general
67
red man syndrome
diffuse flushing from vancomycin
68
how to prevent red man syndrome
pretx w antihistamines and slow infusion rate
69
30S inhibitors
aminoglycosides(bacteriCidal) and tetracycline (bacteriosTatic)
70
50s inhibitors
chloramphenicol, clindamycin, erythromycin (macrolides), linezolid
mostly bacteriostatic
71
aminoglycosides
GNATS - gentamicin, neomycin, amikacin, tobramycin, streptomycin
72
aminoglycosides MOA
block protein synth at 30S - bactericidal
inhibit formation of initiation complex (A initates alphabet) --> mRNA misreading
block translocation
require O2 for uptake (aminO2glycosides)
73
aminoglycosides clinical use
severe gram negative rod infections
| synergistics with beta-lactams
74
aminoglycoside for bowel surgery
neomycin
75
aminoglycoside toxicity
NNOT - nephrotoxicity, neuromusc blockage, ototoxicity, teratogen
76
aminoglycoside plus cephalosporin
nephrotoxicity
77
aminoglycoside plus loop diuretics
ototoxicity
78
aminoglycoside resistance
transferase enzymes inactive drug via acetylation, phosphorylation or adenylation
79
tetracyclines
tetracycline, doxycycline, demeclocycline, minocycline
80
demeclocycline
ADH antagonist - diuretic in SIADH
81
tetracyclines MOA
block protein synth @ 30S; bacteristatic
| prevent attachement of aminoacyl-tRNA - limited CNS penetration
82
doxycycline
fecally eliminated - used in pts w/ renal failure
83
tetracycline warnings
dont take with milk, antacides or iron-containing preps bc divalent cations inhibit absorption in gut
84
tetracycline clinical use
borrelia burgdorferi, m. pnuemoniae
| acumulate intracellularly = very effectives vs rickettsia and chlamydia
85
tetracycline toxicity
GI, discolor teeth + inhibit bone growth in kids, photosensitivity
86
tetracycline CI
preggers
87
tetracycline resistance
decrease uptake in cells or increase efflux by plasmid-encoded transport pumps
88
macrolides
azithryomycin, erthryomycin, clarythromycin
89
macrolides MOA
```
block protein synth at 50S - bacteriostatic
block translocation (macroSLIDES)
bind 23S rRNA of 50S ribosomal subunit
```
90
macrolides clinical use
atypical penuomnia (mycoplasma, chalmydia, legionella), STD (chlamydia), gram pos cocci (step infections in pts allergic to penicillin)
91
macrolides toxicity
MARO - motility issues, arrhythmia due to QT prolongation, acute cholestatic hepatitis, rash, eosinophilia
92
macrolides increases serum concentration of
theophyllines, oral anticoagulants
93
macrolides resistance
methylation of 23S rRNA binding site
94
chloramphenicol MOA
blocks protein synth at 50S - bacteriostatic
| blocks peptidyl transferase
95
chloramphenicol clinical use
meningitis (h flu, n. men, strep pneumo)
| conserv use to to toxicity but cost allows use in developing countries
96
chloramphenicol toxicity
anemia (dose), aplastic anemia
97
gray baby syndrome
chloramphenicol toxicity
| premature infants lack liver UDP-glucoronyl transferase
98
chloramphenicol resistance
plasmid-encoded acetyl transferase inactivates drug
99
clindamycin MOA
blocks protein synth at 50 S - bacteriostatic
| blocks peptide transfer (translocation)
100
chloramphenicol clinical use
anaerobic (bact fragilis, c perf) infections in aspiration pneumonia or lung abscesses
oral infections with mouth anaerobes
101
treats anaerobes above the diaphragm
chloramphenicol
102
treats anaerobes below the diaphram
metronidazole
103
clindamycin toxicity
pseudomembranous colitis (c diff growth), fever, diarrhea
