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Microbiology > Antimicrobial therapy > Flashcards

Antimicrobial therapy Flashcards

1
Q

Antimicrobial therapy - groups

A
  1. Cell wall synthesis
  2. Folic acid synthesis
  3. DNA topoisomerases
  4. Damage DNA
  5. mRNA synthesis
  6. Protein synthesis
  7. daptomycin
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2
Q

Antimicrobial therapy - Cell wall synthesis drugs - divided to

A
  1. Peptidogylcan synthesis drugs

2. Peptidoglycan cross linking

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3
Q

Antimicrobial therapy - peptidoglycan cross linking - Groups and drugs

A
  1. Penicillinae sensitive penicillins (amoxillin, ampicillin, Penicillin G and V)
  2. Penicillinase-resistant penicillins (Dicloxacillin, Nafcillin, Oxacillin, Methcillin)
  3. Antipseudomonals (Piperacillin, Ticarcillin)
  4. Cephalosporins (I-V)
  5. Carbapenems (Doripenem, Ertapenem, Imipenem, Meropenem)
  6. Monobactams (Aztreonam)
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4
Q

Antimicrobial therapy - Penicillinae sensitive penicillins - drugs

A
  1. amoxillin
  2. ampicillin
  3. Penicillin G and V
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5
Q

Prototype β-lactam antibiotics

A

Penicillin G and V

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6
Q

Penicillin G vs V

A

Penicillin G –> IV and IM form

Penicillin V –> Oral

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7
Q

Penicillin G and V - mechanism of action

A

D-Ala-Ala analog –> Bind penicillin-binding proteins (transpeptidas) –> blocks trasnpeptisase cross linking of peptidoglycan in cell wall –> inhibits cell wall synthesis –> Activate autolytic enzyme
BACTERICIDAL

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8
Q

Penicillin G and V - clinical use

A

gram + cocci and robs, gram (-) cocci, spirochetes:

  1. gram (+) organisms (S. pneumoniae, S.pygoenes, Actinomyces)
  2. gram (-) cocci (mainly N. meningitidis)
  3. spirochetes (mainly T. pallidum)
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9
Q

Penicillin G and V - toxicity

A
  1. Hyperesensitivity reactions

2. Hemolytic anemia

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10
Q

Penicillin G and V - resistance

A

Penicillinae in bacteria (a type of β-lactamase) cleaves β-lactam ring

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11
Q

aminopenicillins - drugs

A
  1. amoxillin

2. ampicillin

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12
Q

aminopenicillins (amoxicillin, ampicillin) - mechanism of action

A

same as penicillin but WIDER SPECTRUM

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13
Q

aminopenicillins (amoxicillin, ampicillin) - clinical use

A 
extended spectrum penicillin:
1. H. infl   2. H. pylori  3. E. coli 
4. Listeria  5. Proteus  6. Salmonella
7. Shigella  8.  Entetococci 
MNEMONIC : HHELPSS + enterococci
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14
Q

aminopenicillins (amoxicillin, ampicillin) - toxicity

A
  1. hypersensitivity reactions
  2. rash
  3. pseudomembranous colitis
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15
Q

aminopenicillins (amoxicillin, ampicillin) - mechanism of resistance

A

penicillinase in bacteria (a type of β-lactamase) cleaves β-lactams ring–> combine with clavulanic acid

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16
Q

Penicillinase-resistant penicillins - drugs

A
  1. Dicloxacillin
  2. Nafcillin
  3. Oxacillin
  4. Methcillin
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17
Q

Penicillinase-resistant penicillins - mechanism of action

A

same as penicillin

NARROW SPECTRUM AND PENICILLINASE RESISTANT

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18
Q

Penicillinase-resistant penicillins - mechanism of penicillinase resistance

A

Bulky R group blocks blocks access of β-lactase to lactam ring

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19
Q

Penicillinase-resistant penicillins - drugs and clinical use

A
  1. Dicloxacillin2. Nafcillin 3. Oxacillin 4. Methcillin

S. aureus (except MRSA)

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20
Q

MRSA - mechanism of resistance

A

altered penicillin binding protein target site

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21
Q

Penicillinase-resistant penicillins - toxicity

A
  1. hypersensitivity reactions

2. interstitial nephritis

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22
Q

Antipseudomonals - drugs

A

Piperacillin, Ticarcillin

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23
Q

Antipseudomonals - mechansism of action

A

same as penicillin

Extended spectrum

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24
Q

Antipseudomonals - clinical use

A
  1. psudomonas spp and gram-negative robs

2. gram (-) robs

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25
Q

Antipseudomonals - toxicity

A

hypersensitivity reaction

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26
Q

Antipseudomonals - resistance

A

susceptible to penicillinase –> use with β-lactamase

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27
Q

β-lactamase inhibitors - drugs

A
  1. clavulanic acid
  2. sulbactam
  3. tazobactam
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28
Q

β-lactamase inhibitors - use

A

often added to penicillin antibiotics to protect the antibiotic from destruction by β-lactamase (penicillinase)

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29
Q

Cephalosporins - drugs

A

1st generation –> cefazolin, cephalexin
2nd generation –> cefoxitin, cefaclor, cefuroxamine
3rd generation –> ceftriaxone, cefotaxime, ceftazidime
4th generation –> cefepime
5th generation –> ceftraroline

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30
Q

Cephalosporins - mechanism of action

A

β- lactam drugs that inhibit cell wall synthesis but are less susceptible to penicillinases - BACTERICIDAL

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31
Q

organisms typically not covered by Cephalosporins?

A

mnemonic: LAME
Listeria, Atypicals (Chlamydia, Mycoplasma) MRSA, Entrococci
exception. Ceftaroline (5th) covers MRSA

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32
Q

1st generation cephalosporins - drugs and clinical use

A 
cefazolin, cephalexin 
1. gram + cocci 
2. Proteus
3. E. coli
4. Klebsiella 
cefazolin used prior to surgery to prevent S. aureus wound infection
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33
Q

cefazolin used prior to surgery to

A

prevent S. aureus wound infection

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34
Q

2nd generation - drugs and clinical use

A

cefoxitin, cefaclor, cefuroxamine

  1. like 1st generation (gram + cocci, proteus, E.coli, Klebsiella)
  2. H. infuenzae
  3. Enterobacter aerogenes
  4. Neisseria spp
  5. Serratia marcescens
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35
Q

3rd generation - drugs and clinical use

A

ceftriaxone, cefotaxime, ceftazidime
serious gram (-) infections resistant to other β-lactams
- ceftriaxone –> meningitis, gonnorrhea, disseminated Lyme disease
- Ceftazimide –> Pseudomonas

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36
Q

4th generation - drugs and clinical use

A

cefepime
gram (-) organism, with high activity against Pseudomonas
2. gram (+)

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37
Q

5th generation - drugs and clinical use

A 
ceftaroline
1. broad gram (+)
2. borad gram (-)
INCLUDING MRSA 
DOES NTO COVER PSEUDOMONAS
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38
Q

Cephalosporins - toxicity

A
  1. hypersensitivity reactions
  2. autoimmune hemolytic anemia
  3. disulfiram-like reaction
  4. vitamin K deficiency
  5. exhibit cross-reactivity with penicillins
  6. Increases aminoglycosides mediated nephrotoxicity
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39
Q

Cephalosporins - mechanise of resistance

A

structural change in penicillin-binding proteins (transpeptidase)

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40
Q

Carbapenems - drugs

A
  1. Imipenem
  2. Meropenem
  3. Doripenem (newer)
  4. Ertapenem (newer)
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41
Q

Carbapenems - mechanism of action

A

broad spectrum, β-lactamase-resistant β-lactam
ALWAYS ADMINISTRATED WITH CILASTATIN (inhibitor of renal dehydropeptidase I) to decrease inactivation of drug in renal tubule –> meropenem is stable to cilastatin

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42
Q

cilastatin - mechansim of action

A

inhibitor of renal dehydropeptidase I

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43
Q

Carbapenems - clinical use

A
  1. Gram (+) cocci
  2. Gram (-) robs
  3. anaerobes
    WIDE spectrum but significant side effects limit use of life threatening infection or after other drugs have failed
    Ertapenem has limited pseudomonas coverage
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44
Q

Carbapenems - toxicity

A
  1. GI distress
  2. skin rash
  3. CNS toxicity (seizurs) at high plasma levels (less risk with meropenem)
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45
Q

Monobactams - drugs

A

Aztreonam

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46
Q

Monobactams (Aztreonam) - mechansim of action

A

Bind penicillin-binding proteins 3 (transpeptidas) –> blocks trasnpeptisase cross linking of peptidoglycan in cell wall –> inhibits cell wall synthesis –> Activate autolytic enzyme
LESS SUSCEPTIBLE TO β-lactamases

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47
Q

Monobactams (Aztreonam) - 2 special characteristics

A
  1. no cross-allergenicity with penicillins

2. Synergistic with aminoglycosides

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48
Q

Monobactams (Aztreonam) - clinical use

A
  1. Gram (-) robs ONLY (no anaerobesm no gram (+))

For penicillin allergic patients and those with renal insufficiency who cannot tolerate aminoglycosides

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49
Q

Monobactams (Aztreonam) - side effects

A

usually nontoxin –> occasional GI upset

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50
Q

Monobactams (Aztreonam) - β-lactamases

A

less susceptible

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51
Q

Carbapenems (Doripenem, Ertapenem, Imipenem, Meropenem) - β-lactamases

A

resistant

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52
Q

Antimicrobial therapy - Cell wall synthesis drugs - divided to

A
  1. Peptidogylcan synthesis drugs

2. Peptidoglycan cross linking

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53
Q

Antimicrobial therapy - Cell wall synthesis drugs - groups and drugs

A

glycopeptides:
1. Bacitracin
2. Vancomycin

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54
Q

Vancomycin - mechanism of action

A

inhibits cell wall peptidoglycan formation by binding D-ala D-ala portion of cell wall precursors
BACTERICIDAL
not susceptible to β-lactamases

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55
Q

Vancomycin - clinical use

A 
gram (+)  bugs only:
serious Multidrug resistance organisms, including:
- MRSA 
- S. epidermidis 
- Clostiridium difficle (oral)
- Enterococcus species
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56
Q

Vancomycin - toxicity

A

well tolerated

  1. nephrotoxicity
  2. ototoxicity
  3. thrombophlebitis
  4. red man syndrom (diffuse flushing)
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57
Q

red man syndrom - appearance, caused by, solution

A
  • diffuse flushing
  • it is caused by vancomycin
  • pretreatment with antihistamines and slow infusion rate
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58
Q

Vancomycin - mechanism of resistance

A

occurs in bacteria via amino acid modification of D-ala D-ala to D-ala D-lac

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59
Q

Antimicrobial therapy - DNA topoisomerases - drugs

A

Fluroroquinolones: (-FLOXACIN) + enoxacin

  1. CIPRO-
  2. NOR-
  3. LEVO-
  4. O-
  5. MOXI
  6. GEMI-
  7. ENOXACIN
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60
Q

Fluroroquinolones - drug that i not -floxacin

A

enoxacin

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61
Q

Fluroroquinolones - mechanism of action

A

inhibit prokaryotic enzymes topoisomerase II (DNA gyrase) and topoisomerase IV
BACTERICIDAL

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62
Q

Fluororoquinolones - clinical use

A
  1. gram (-) robs of urinary and GI tracts (including Pseudomonas)
  2. Neisseria
  3. some gram (+)
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63
Q

Fluororoquinolones - toxicity

A
  1. GI upset
  2. superinfections
  3. skin rash
    4 .headache/dizziness
  4. leg cramps and myalgias (less commonly)
  5. Prolonged QT
  6. tendonitis or tendon rupture (if >60 or prednisone)
  7. contraindicated in pregnancy, nursing mothers, children under eighteen –> possible damage to cartilage
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64
Q

Fluororoquinolones - mechanism of resistance

A
  1. chromosome encoded mutation in DNA gyrase
  2. plasmid mediated resistance
  3. efflux pumps
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65
Q

Antimicrobial therapy - damage DNA drug

A

metronidazole

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66
Q

metronidazole - mechanism of action

A

Forms toxic free radical metavolites in the bacterial cell that damage DNA.
BACTERICIDAL, ANTIPROTOZOAL

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67
Q

metronidazole - clinical use

A
  1. Giardia
  2. Entamoeba
  3. Trichomonas vaginalis
  4. Garndenella vaginalis
  5. Anaerobes (Bacteroides, C. difficile)
  6. H. pylori
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68
Q

metronidazole - adverse effects

A
  1. Disulfiram-like reaction (severe flushing, tachycardia, hypertension) with alcohol
  2. headache
  3. metallic taste
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69
Q

Daptomycin - mechanism of action

A

lipopeptide that disrupt cell membrane of gram (+) cocci

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70
Q

Daptomycin - clinical use

A
  1. S. aureus SKIN infection (esp MRSA)
  2. bacteremia
  3. endocarditis
  4. VRE
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71
Q

Daptomycin to pneumonia

A

not used –> avidly binds to and is inactivated by surfactant

72
Q

Daptomycin - toxicity

A
  1. Myopathy

2. rhabdomyolysis

73
Q

Antimicrobial therapy - protein synthesis - divisions and drugs

A

50S –> 1. Chloramphenicol 2. Clindamycin 3. Linezolid 4. Macrolides 5. Streptogramins
30S –> 1. aminoglycosides 2. Tetracyclines

74
Q

Antimicrobial therapy - protein synthesis - mechanism of action

A

specifically target smaller bacterial ribosome (70S=30S+50S), leaving human ribosome (80S) unaffected

75
Q

Aminoglycosides - drugs

A
  1. Gentamycin
  2. Neomycin
  3. Amikacin
  4. Tobramycin
  5. Streptomycin
76
Q

Aminoglycosides - mechanism of action

A
  • irreversible inhibition of initiation complex through binding of the 30S subunit
  • mRNA misreading
  • Block translocation
    BACTEROCIDAL /REQUIRE O2 FOR UPTAKE
77
Q

Aminoglycosides - clinical use

A
  1. severe gram (-) rob infection
  2. Synergistic with β-lactam antibiotics
  3. Neomycin for bowel surgery
78
Q

Aminoglycosides - side effects

A
  1. nephrotoxicity (worse with cephalosporins)
  2. Neuromascular blockage
  3. Ototoxicity (esp with loop diuretics)
  4. Teratogen
79
Q

Aminoglycosides - ototoxicity espc with

A

loop diuretics

80
Q

Aminoglycosides - mechanism of resistance

A

Bacterial tranferase enzymes inactivate the drug by acetylation, phosphorylation, or adenylation

81
Q

Tetracyclines - drugs

A
  • CYCLINE
  • tetracycline
  • doxycycline
  • minomycline
82
Q

Tetracyclines - mechanism of action

A

bind 30S (A-site tRNA binding) and prevent attachment of aminoacyl-tRNA
BACTERIOSTATIC
LIMITED CNS PENETRATION

83
Q

Tetracyclines - cns

A

limited penetration

84
Q

doxycycline - special characteristic

A

it is fecally eliminated and can be used in patients with renal failure

85
Q

Tetracyclines - co-administrations

A

do not take tetracyclines with milk (Ca2+), antiacids (Ca2+ or Mg2+), pr iron-containing preparations –> divalent cations inhibit drug’s absorption in the gut

86
Q

Tetracyclines - clinical use

A
  1. Borrelia bugdorferi
  2. M. pneumoniae
  3. Rickettsia
  4. Chlamydia
  5. acne
  6. Ehrichiosis/Anaplasmosis
  7. Q fever
87
Q

Tetracyclines - effective against Rickettsia and chlamydia because of

A

their ability to accumulate intracellulary

88
Q

Tetracyclines - renal failure

A

doxycycline is fecally eliminated and can be used in patients with renal failure

89
Q

Tetracyclines - toxicity

A
  1. GI distress
  2. discoloration of teeth and inhibition of bone growth in children
  3. photosensitivity
  4. Contraindicated in pregnancy
90
Q

Tetracyclines - mechanism of resistance

A

decreased uptake or increased efflux out of bacterial cells by plasmid-encoded transport pumps

91
Q

Antimicrobial therapy - protein synthesis - 30S inhibitors (and bactericidal or bacteriostatic)

A 
1. Aminoglycosides (bactericidal)
2 Tetracyclines (bacteriostatic)
92
Q

chloramphenicol - mechanism of action

A

block peptidyltranferase at 50S ribosomal subunit

Bacteriostatic

93
Q

chloramphenicol - clinical use

A
  1. meningitis (H. infl, N. meningitis, S. pneumoniae)
  2. Rocky Montain spoted fever (R. ricketsi)
    Limited use owing to toxicities but often still used in developing countries (low cost)
94
Q

chloramphenicol - toxicity

A
  1. anemia (dose dependent)
  2. aplastic anemia (dose independent)
  3. gray baby syndrome
95
Q

chloramphenicol - gray baby syndrome - mechanism

A

in premature infants because they lack liver UDP-glucuronyl tranferase

96
Q

chloramphenicol - mechanism of resistance

A

plasmid-encoded acetyltranferase inactivates the drug

97
Q

Clindamycin - mechanism

A

blocks peptide transfer (translocation) at 50S ribosomal subunit.
BACTERIOSTATIC

98
Q

Clindamycin - clinical use

A
  1. anaerobic infections in aspiration pneumonia, lung abscess, oral infection
  2. invasive A streptococcal infection
  3. Gardenella vaginalis
99
Q

metronidazole vs clincamycin according to clinical use

A

treats anaerobic infection below diaphragm with metronidazole and above diaphragm with clindamycin

100
Q

Clindamycin - toxicity

A
  1. pseudomembranous colitis
  2. fever
  3. diarrhea
101
Q

Oxalinezolid - drugs

102
Q

Linezolid - mechanism of action

A

it inhibits protein synthesis by binding to 50S subunit and preventing formation of the initiation complex

103
Q

Linezolid - clinical use

A

gram (+) species MRSA and VRE

104
Q

Linezolid - toxicity

A
  1. bone marrow suppression (esp thrmbocytopenia)
  2. peripheral neuropathy
  3. seretonin syndrome
105
Q

Linezolid - mechanism of resistance

A

point mutation of ribosomal RNA

106
Q

Macrolides - drugs

A
  1. Azythromycin
  2. Clarithromycin
  3. Erythromycin
107
Q

Macrolides - mechanism of action

A

bind to the 23S rRNA of the 50S ribosomal subunit
–> inhibit protein synthesis by blocking translocation
BACTERIOSTATIC

108
Q

Macrolides - clinical use

A
  1. Atypical pneumonias (Mycoplasma, chlamydia, legionalla
  2. STI (chlamydia)
  3. Gram (+) cocci (streptococcal infections in patients allergic to penicillin)
  4. B. pertusis
109
Q

Macrolides - resistance

A

methylation of 23S rRNA-binding site prevents binding of drug

110
Q

Macrolides - side effects

A
  1. GI uspet 2
  2. Arrhytmia (long QT)
  3. Acute cholestatic hepatitis
  4. Rash
  5. eosinophilia
  6. increased serum levels of theophyllines, oral anticoagulants
  7. inhibit P-450 (clarithromycin and erythrmicycin)
  8. contraindicated in pregnancy (embryotoxic)
111
Q

macolides - P-450

A

clarithromycin and erythrmicycin inhibit P-450

112
Q

Antimicrobial therapy - protein synthesis - divisions and drugs (bactericidal or bacteriostatic)

A

50S –> 1. Chloramphenicol (bacteriostatic) 2. Clindamycin (bacteriostatic) 3. Linezolid (variable) 4. Macrolides (bacteriostatic) 5. Streptogramins
30S –> 1. aminoglycosides (bactericidal 2. Tetracyclines (bacteriostatic)

113
Q

Streptogramins - drugs

A
  1. Dalfopristin

2. Quinupristin

114
Q

Antimicrobial therapy - Folic acid synthesis - drugs

A
  1. Sulfonamides: a. sulfadiazine b. sulfamethoxazole (SMX)
    c. sulfisoxazole
  2. Trimethoprim (or pyrimethamine)
  3. dapsone
115
Q

Tetrahydrofolic acid (THF) synthesis pathway

A 
PABA + Pteridine --> Dihydropteroic acid (Dihydropteroate syntase) --> Didhydrofolic acid --> 
Tetrahydrofolic acid (THF) (Dihydrofolate reductase)
116
Q

Tetrahydrofolic acid (THF) can give rise to

A
  1. Purines (DNA, RNA)
  2. Thymidine (DNA)
  3. Methionine (Protein)
117
Q

Trimethoprim - mechanism of action

A

inhibits bacterial dihydrofolate reductase

BACTERIOSTATIC

118
Q

dihydrofolate reductase - action

A 
Didhydrofolic acid --> 
Tetrahydrofolic acid (THF)
119
Q

Trimethoprim - clinical use

A

in combination with sulfonamides (TMP-SXM) –> seqential block of folate syntesis –>
1. UTI 2. Shigella 3. Salmonella 4. P. jorovecii (treatment and prophyaxis) 5. toxoplasmosis prophylaxis

120
Q

Trimethoprim - toxicity

A
  1. megaloblastic anemia
  2. leukopenia
  3. granulocytopenia
    MAY ALLEVIATE WITH SUPPLEMENTAL FOLINIC ACID
121
Q

Tetrahydrofolic acid (THF) synthesis pathway - PABA?

A

Para-aminobenzoic acid

122
Q

Tetrahydrofolic acid (THF) synthesis pathway

A 
PABA + Pteridine --> Dihydropteroic acid (Dihydropteroate syntase) --> Didhydrofolic acid --> 
Tetrahydrofolic acid (THF) (Dihydrofolate reductase)
123
Q

Antimicrobial therapy - Folic acid synthesis - drugs

A
  1. Sulfonamides: a. sulfadiazine b. sulfamethoxazole (SMX)
    c. sulfisoxazole
  2. Trimethoprim (or pyrimethamine)
124
Q

Sulfonamides - drugs

A

a. sulfadiazine
b. sulfamethoxazole (SMX)
c. sulfisoxazole

125
Q

Sulfonamides - mechanism of action

A 
PABA antimetobolites (analog) inhibit dihydropteroate synthase 
BACTERIOSTATIC (BACTERICIDAL when combined with trimethoprim)
126
Q

Sulfonamides - clinical use

A
  1. Gram-positives
  2. Gram-negatives
  3. Nocardia
  4. Chlamydia
  5. simple UTI (TRIPLE SULFAS or SMX)
127
Q

Sulfonamides - toxicity

A
  1. hypersensitivity 2. G6PD hemolysis
  2. nephrotoxicity (tumbulointestinal nephritis)
  3. photosensitivity 5. kernicterus (infants)
  4. displace other drug from albumin (eg. warfarin)
128
Q

Sulfonamides displaces other drugs from albumin - example

129
Q

Sulfonamides - nephrotoxicity?

A

tumbulointestinal nephritis

130
Q

Sulfonamides - mechanism of resistance

A
  1. altered enzyme (bacterial dihydropteroate syntase)
  2. decreased uptake
  3. increased PABA synthesis
131
Q

Dapsone mechanism of action and side effects

A

similar to sulfonamides, but structurally distinct agent

Hemolysis if G6PD deficiency

132
Q

Dapsone clinical use

A
  1. Leprosy (leptromatous and tuberculoid)

2. Pneumocystis jorovecii prophylaxis

133
Q

botulism treatment

134
Q

pseudomembranous colitis - treatment

A

metronidazoleo or oral vancomycin

For recurrent cases, consider repeating prior regimen, fidaxomicin, or fecal microbiota transplant

135
Q

Listeria monocytogenes - treatment

A
  1. gastroenteritis is self limited

2. ampicillin in infants, immunocompromised, and the elderly as empirical treatment of meningitis

136
Q

actinomyces vs Nocardia according to treatment

A

MNEMONIC: SNAP –> Sulfa - Nocardia / Actinom - Penicillin
Acinomyces –> penicillin
Nocardia –> sulfonamides

137
Q

C. tetani - therapy

A

Prevent with tetanus vaccine

treat with antitoxin +/- vaccine booster and diazepam (for muscle spasms)

138
Q

neisseria gonococci vs neisseria meningitis - treatment

A

neisseria gonococci –> ceftriaxone + (azithromycin or doxycycline) for possible chlamydial coinfection
neisseria meningitis –> ceftraxone or penicillin G

139
Q

neisseria gonococci vs neisseria meningitis - prevention

A

neisseria gonococci –> condoms (for STD), erythromycin ointment (neonatal transmision)
neisseria meningitis –> Rifampin, ciprofloxacin or ceftriaxone prophylaxis in close contacts

140
Q

H. influenza - treatment/prophylaxis

A
  1. mucosal infection –> amoxicillin +/- clavulanate
  2. meningitis –> ceftriaxon.
    prophylaxis –> rifampin
141
Q

Legionella - treatment

A

macrolide or quinolone

142
Q

Pseudomonas aeroginosa - treatment

A
  1. extended spectrum β-lactams (eg piperacillin, ticarcillin, cafepime)
  2. Carbapenems (eg imipenem, meropenem)
  3. Monobactams (eg aztreonam)
  4. Fluoroquinolones (eg ciprofloxacin)
  5. Aminoglycosides (eg. gentamycin, tobramicin)
  6. For multidrug resistant stains –> colistin, polymyxin B
143
Q

typhoid fever - treatment

A

ceftriaxone or flouroquinolone

144
Q

Helicobacter pylori - treatment

A

MC initial treatment:

PROTON PUMP INHIBITOR + CLARITHROMYCIN + AMOXICILLIN (or metronidaxzole if penicillin allergy)

145
Q

Lyme disease - treatment

A
  1. doxycycline

2. ceftriaxone

146
Q

how to prevent congenital syphilis

A

treat mother early in pregnancy, as placental transmission occurs after first trimester

147
Q

patients with + culture of Streptococcus agalactiae –>

A

receive intrapartum penicillin for prophylaxis

148
Q

Gardnerella vaginalis - treatment

A

metronidazole or clindamycin

149
Q

Typhus treatment

A

all vector-borne illness - rash common and rash rare diseases –> doxycycline

150
Q

Q fever treatment

A

all vector-borne illness - rash common and rash rare diseases –> doxycycline

151
Q

Chlamydia - treatment

A

azythromycin (favored because in time treatment) or doxycycline

152
Q

Lymphogranuloma venereum - treatment

A

doxycycline

153
Q

Mycoplasma pneumoniae - treatment

A

macrolides, doxycycline, or fluoroquinolone

154
Q

antimicrobial prophylaxis - high risk for endocarditis and undergoing surgical or dental procedures

A

amoxicillin

155
Q

antimicrobial prophylaxis - exposure to gonorrhea

A

ceftriaxone

156
Q

antimicrodial prophylaxis -history of reccurent UTIs

157
Q

antimicrobial prophylaxis - exposure to meningococcal infection

A

ceftriaxone, ciprofloxacin or rifampin

158
Q

antimicrodial prophylaxis - Pregnant woman carrying group B strep

A

Penicillin G

159
Q

antimicrobial prophylaxis - prevention of gonococcal conjuctivitis in newborn

A

Erythomycin oitment

160
Q

antimicrobial prophylaxis - prevention of postsurgical infection due to S. aureus

161
Q

antimicrobial prophylaxis - prophylaxis of strep pharyngitis in child with prior rheumatic fever

A

Benzathine penicillin G
or
oral penicillin V

162
Q

antimicrobial prophylaxis - Exposure to syphilis

A

Benzathine penicillin G

163
Q

antibiotic for bowel surgery

164
Q

Antibiotics to avoid in pregnancy (and why)

A
  1. Sulfonamides –> Kernicterus
  2. Amniglycosides –> Ototoxicity
  3. Fluoroquinolones –> Cartilage damage
  4. macrolides –> embryotoxic
  5. tetracyclines –> DIscolored teeth, inhibiton of growth
  6. Chloramphenicol –> Gray babe syndrome
  7. Griseofluvin –> teratogenic
  8. Ribavirin (antiviral)
165
Q

non bacterial antibiotics to avoid in pregnancy

A
  1. Griseofluvin –> teratogenic

2. Ribavirin (antiviral)

166
Q

antibiotic that causes kernicterus if used during pregnancy

A

Sulfonamides

167
Q

Treatment of highly resistant bacteria

A

MRSA: vancomycin, daptomycin (esp skin), linezolid, tigecycline, ceftaroline
VRE: linezolid and streptogramins (quinupristin, dalfopristin)
Multidrug-resistant P. aeruginosa: polymixins B and E (Colistin)
Multidrug-resistant Acinetobacter baumannii: polymixins B and E (Colistin)

168
Q

Treatment of MRSA

A

vancomycin, daptomycin (esp skin), linezolid, tigecycline, ceftaroline

169
Q

treatment of VRE

A

linezolid and streptogramins (quinupristin, dalfopristin)

170
Q

treatment Multidrug-resistant P. aeruginosa

A

polymixins B and E (Colistin)

171
Q

treatment of Multidrug-resistant Acinetobacter baumannii

A

polymixins B and E (Colistin)

172
Q

antibiotics - prophylaxis in HIV patients (and why)

A

CD4 under 2 hundred –> TMP-SMX (pneumocysts)
CD4 under 1 hundred –> TMP-SXM (pneumocysts and toxoplasmosis)
CD4 under fifty –> Azithromycin or clarythromycin (M. avium complex)

173
Q

antibiotics - prophylaxis in HIV patients (and why) - under 2 hundred

A

TMP-SMX (pneumocysts)

174
Q

antibiotics - prophylaxis in HIV patients (and why) - under 1 hundred

A

TMP-SXM (pneumocysts and toxoplasmosis)

175
Q

antibiotics - prophylaxis in HIV patients (and why) - under fifty

A

Azithromycin or clarythromycin (M. avium complex)

Microbiology (25 decks)

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