Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

D1 Host and Defense > Antimicrobials 1 -Smith > Flashcards

Antimicrobials 1 -Smith Flashcards

(83 cards)

Start Studying
1
Q

describe the characteristics of gram (+) cells and antibiotics?

A

-have a cell wall composed of thick peptidoglycan layer which this is the target of many antimicrobials

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

describe the characteristics of gram (-) cells and antibiotics?

A
  • have a thin peptidoglycan cell wall and they have an LPS cell membrane outside
  • the penicillin binding proteins are hard to target with antimicrobials b/c of the cell membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what the the structure of B lactam antimicrobials?

A

double ring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

how do B lactam antimicrobials work?

A
  • they resemble D- Alanine end of the peptide that serves as a substrate for transaminopeptidase enzymes
  • essentially B-lactam’s are inserted into the cell wall
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

the be effective B lactam’s must be what 4 things?

A
  1. evade bacterial defenses
  2. penetrate outer cell layers to inner cytoplasmic membrane
  3. keeps it’s B lactam ring intact
  4. bind to transpeptidase (penicillin binding protein- PBP)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what do gram (+) organisms have outside the cell wall that can inactivate penicillin?

A

penicillinases (B lactamases)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are transpeptidase enzymes and what is their function?

A

-they crosslink adjacent glycan chains by removing the terminal D-alanine residue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how B lactams

A

B-lactams bind to the active site of penicillin binding protein and prevent transpeptidation. The bacteria than can not make new peptidoglycan autolyses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

B-lactam drugs are only effective on what type of organisms?

-they are inactive against?

A
  • rapidly dividing organisms

- inactive against: fungi, viruses, mycobacteria (organisms without a peptidoglycan later)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are the 5 types of B lactam antimicrobials?

A
  1. natural penicillins
  2. aminopenicillins = “extended spectrum penicillins”
  3. Penicullinase-resistant penicillins = “antistaphylococcal penicullin)
  4. Anti pseudomonal penicillins
  5. Cephalosporins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are the types of Natural Penicillins?

A
  1. Penicillin G

2. Penicillin VK

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the mechanism of Natural penicillins

A
  • Inhibits transpeptidase (penicillin-binding protein)

- Activates autolytic enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

are Natural penicillins bacteriostatic or bacteriocidal?

A

bacteriocidal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

effect of penicillinase onNatural penicillins ?

A

-they are sensitive to penicillinase (B lactamases)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Natural Penicillins are used to clinically treat what?

A

Streptococci, penumococci, enterococci (w aminoglycosides) miningococci, treponema palladium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Natural Penicillins are effective against what type of organisms?

A

gram + cocci and less on gram (-) except nisseria species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Toxicity of Natural Penicillins?

A

hypersensativity reactions

-hemolytic anemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are the penicillinase-resistant penicillins?

A
  • methicillin
  • Nafcillin
  • oxacillin
  • dicloxacillin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is the mechanism of penicillinase-resistant penicillins?

A
  • Inhibits transpeptidase (penicillin-binding protein)
  • Activates autolytic enzymes
  • bacteriocidal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are the 3 Beta-lactamase inhibitors?

A
  1. clavulanate
  2. sublactam
  3. tazobactam
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is unasyn?

A

ampicillin + sublactam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is the spectrum of penicillin?

A

narrow spectrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

non MRSA Staphylococcal infections are treated with what?

A

-Naficillin - “Naf for Staph” - this is a penicillinase resistant penicillin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are examples of Aminopenicillins?

A
  • ampicillin

- axomicillin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
mechanism of Aminopenicillins?
- Inhibits transpeptidase (penicillin-binding protein) - Activates autolytic enzymes - bacteriocidal
26
spectrum of Aminopenicillins?
-wide spectrum when combined with clavulanic acid
27
effect of B lactamase on Aminopenicillins ?
penicillinase sensitive - paired w clavulanic acid to inhibit this effects
28
what type of organisms are Aminopenicillins effective against?
gram + bacteria and gram (-) rods
29
what is the drug of choice for prophylaxis of infective endocarditis?
amoxicillin (Aminopenicillin) or cephalexin if allergic
30
what is the drug of choice for Listeria monocytogenes and enterococci?
Aminopenicillins
31
what is a toxicity risk of Aminopenicillins?
pseudomembranous colitis
32
how does probenecid effect the clearance of Ampicillin?
probenecid slows renal excretion of Ampicillin
33
what is the mnemonic for Ampicillin?
'AMPing up AMO HELPS kill a wide spectrum of enterococci'
34
what can inactivate ampicillin when mixed in IV solutions?
hydrocortisone
35
what are the Anti-pseudomonal Penicillins
``` Anti-pseudomonal Penicillins -Ticarcillin -Carbenicillin -Piperacillin TCP: Takes Care of Pseudomonas ```
36
mechanism of Anti-pseudomonal Penicillins and spectrum of activity?
- Inhibits transpeptidase (penicillin-binding protein) - Activates autolytic enzymes - bacteriocidal - extended spectrum
37
is Anti-pseudomonal Penicillins sensitive to penciillinase?
-yes penicillinase sensitive
38
Anti-pseudomonal Penicillins are used to treat what?
pseudomonas and gram (-) rods | -synergistic with aminoglycosides
39
what is the broadest spectrum penicillin?
piperacillin
40
how are cephalosporins excreted?
renally excreted
41
what are the 1st generation cephalosporins?
Cefazolin (IV), Cephalexin | oral
42
what do the 1st generation cephalosporins treat? When are they typically used? Mnemonic:
``` -Gram (+): also some Gram (-) Proteus mirabilis E. coli Klebsiella pneumonia -typically used before surgery Mnemonic: 1st Generation for a PEcK ```
43
what are the second generation cephalosporins?
Cefoxitin Cefaclor Cefuroxime
44
what do the second generation cephalosporins treat?
2nd Gnereration for a HEN PEcK ---gram (-) - Haemophilus Influenza - Enterobacter aerogenes - Neisseria - Proteus mirabilis - E. coli - Klebsiella pneumonia
45
how does penicillinase effect cephalosporins?
cephalosporins = penicillinase resistant
46
what are the 3rd generation cephalosporins?
Ceftriaxone, Cefotaxime, Ceftazidime, cefdinir
47
what do the 3rd generation cephalosporin's treat? that type of organisms? mnemonic?
3rd Generation crosses BBB -Gram positive and gram-negative cocci and gram negative bacilli, -treats :Meningitis, anaerobes, and gonococci, pseudomonas -Mnemonic: Tri to TAX TAZ! (3rd Generation). Third generation individual drugs Pseudomonas (ceftazidine), anaerobes (ceftozoxime), and gonococci (ceftriaxone)
48
What are examples of 4th generation cephalosporins?
Cefepime
49
What do 4th generation cephalosporins treat?
4th Generation Pseudomonas
50
what are examples of 5th generation cephalosporins?
ceftaroline
51
what can 5th generation cephalosporins be used to treat?
MRSA
52
toxicity risk of cephalosporins
- hypersensitivity rxns to increasing toxicity of aminoglycosides - pseudomembranous colitis
53
what is the mechanism of Aztreonam?
- Inhibits transpeptidase (penicillin-binding protein) - Activates autolytic enzymes - bacteriocidal
54
are Aztreonam Penicillins sensitive to penciillinase?
B lactamase resistant
55
Aztreonam is effective against what type of organisms?
gram negative aerobic rods Mnemonic: Aztreonam treats a SPiKe -Serratia, Pseudomonas, klebsiella
56
what is the risk of toxicity of Aztreonam?
pseudomonas colitis - overgrowth of C. difficile
57
when should Aztreonam be used?
Use with 'penicillin-allergic' patients and those with renal | insufficiency who cannot tolerate
58
what can be done to increase the coverage of Aztreonam?
pair it with Vancomycin or clindamycin
59
what are the carbapenems?
- imipenem - meropenem - ertapenem
60
what is the mechanism of carbapenems?
- Inhibits transpeptidase (penicillin-binding protien) - Activates autolytic enzymes - bacteriocidal
61
are carbapenems sensitive to penicillinase?
-penicillinase resistant ( b lackam resistant)
62
what is the drug of choice for enterobacteria?
Carbapenems
63
What is the risk of toxicity for carbapenems?
CNS toxicity
64
Imipenem (carbapenem) must be paired with _______ and why?
imipenum must be paired with cilistatin (an inhibitor of renal dihydropeptidase1) to decrease inactivation in renal tubules
65
how are carbapenems excreted?
renally excreted
66
what is the broadest antibacterial available?
imipenum + cilistatin
67
carbapenems are effective against what type of organisms?
gram positive cocci gram negative rods anaerobes
68
mechanism of vancomycin?
Inhibits cell wall formation by binding D-ala, D- ala portions of cell wall precursors
69
what is vancomycin used to treat?
treats multidrug resistant gram (+): Staphylococcus aureus and Clostridium difficile
70
what is the risk of toxicity of vancomycin?
Nephrotoxicity, Ototoxicity, Thrombophlebitis, Flushing 'red man syndrome' Mnemonic: The Red Man will NOT take Vanco
71
what is the mechanism of Bacitracin?
Blocks peptidoglycan synthesis
72
what is the risk of toxicity of Bacitracin?
Nephrotoxicity Ototoxicity
73
what is the mechanism of Daptomycin
Inserts into cell membrane, forming ion channels that disrupt ionic concentration gradient of bacteria (BACTERICIDAL)
74
Daptomycin is used to treat what?
Vancomycin- and methicillin-resistant Gram (+) bacteria
75
how does amoxicillin effect methotrexate?
amoxicillin dose dependently inhibits renal tubular secretion of methotrexate = high serum levels
76
how is ampicillin administered?
parenterally (IV)
77
Aminopenicillins treat what bugs?
H. influenza, enterics like E. coli, Salmonella, Shigella
78
what are the anti staphylococcal penicillins?
Methicillin, nafcillin, oxacillin, dicloxacillin
79
what happens as the generation of cephalosporins goes from 1 to 5?
the gram positive activity decreases and it becomes more resistant to B-lactamase enzymes
80
what type of cephalosporins do superinfections occur in and why?
--more likely in 2nd, 3rd, and 4th generation cephalosporins b/c they have reduced gram positive activity (particularly against enterococci)
81
what is the first drug of choice for surgical prophylaxis?
cefazolin - a 1st generation cephalosporin
82
are Cephalosporins penacillinase resistant??
yes Cephalosporins are resistant to penicillinase enzymes
83
B lactamase resistant antibiotics?
- penicillinase resistant penicillins( methicillin, nafacillin...etc - cephalosporins - azetreonam - carbapenems

D1 Host and Defense (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions