Module 6: Antimicrobial Agents Flashcards

1
Q

Define antimicrobial agent

A

Chemotheraputic agent used for treatment of infectious diseases

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2
Q

What 4 criteria must an antibiotic have in order to be used?

A
  1. Selective toxicity (kill bacteria, no damage to host cells)
  2. Not cause allergic reaction
  3. Soluble in body fluids and capable of tissue penetration
  4. Microorganisms must not readily develop resistance
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3
Q

What are broad spectrum antibiotics?

A

Affect wide variety of bacteria, gram positive and negative

Must have action against some Enterobacteriaceae to be broad

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4
Q

What are narrow spectrum antibiotics?

A

Affects small group of bacteria

Gram positive OR negative, not both

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5
Q

Define bactericidal

A

Agent kills bacteria

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6
Q

Define bacteriostatic

A

Agent prevents bacteria from multiplying, then body defenses get rid of it

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7
Q

Why would a bacteriostatic agent not be used on immunocompromised patients?

A

There are no body defenses to get rid of the bacteria

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8
Q

What are the 5 possible modes of action an antibiotic may have?

A
  1. Inhibit cell wall synthesis
  2. Inhibit protein synthesis
  3. Inhibit DNA and RNA synthesis
  4. Inhibit cell membrane function
  5. Inhibit other metabolic processes
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9
Q

Why are agents which inhibit the cell wall synthesis of bacteria used? (2)

A
  1. Human cells don’t have a cell wall

2. Peptidoglycan in the bacteria cell wall is unique to bacteria

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10
Q

What is the core component of all cell wall synthesis inhibiting antibiotics? What is it made of?

A

Beta-lactam ring

Made of three carbons and one nitrogen molecules arranged in a ring

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11
Q

What do cell wall synthesis inhibiting antibiotics bind to?

A

Enzymes in the cell wall called Penicillin binding proteins

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12
Q

How do cell wall synthesis inhibiting antibiotics cause bacterial death?

A

The agents bind to cell wall enzymes that are the last stage of peptidoglycan synthesis, which inhibits cross-linking between the proteins
This causes weakness and eventual rupturing

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13
Q

Why are gram negative bacteria usually resistant to beta-lactam antibiotics?

A

They have a lipid layer covering the peptidoglycan layer, protecting it from the antibiotic

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14
Q

What are the 2 major beta-lactam antibiotic groups?

A

Penicillin and cephalosporins

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15
Q

What are the 4 groups of penicillin?

A

Natural, beta-lactamase resistant, extended spectrum, anti-pseudomonal

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16
Q

What are natural penicillins?

A

Penicillin where the original compound is extracted from Penicillium mold
The compound is Penicillin G or Benzylpenicillin

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17
Q

What spectrum does natural penicillin have?

A

Narrow, gram positive with a few gram negative

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18
Q

Is there bacterial resistance to natural penicillin? If so, how does it work?

A

Yes, it can be inactivated by bacteria which produces beta-lactamase (enzyme) which opens the beta-lactam ring

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19
Q

What is the clinical usage of natural penicillin?

A

Penicillin G - injection, resistant to stomach acid
Penicillin V - orally

Usually given with other drugs to improve absorption and retention

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20
Q

What laboratory testing is done in regards to bacterial sensitivity?

A
Penicillin G used to test and applied to all other natural penicillins
EX: Penicillin G is sensitive, so are other penicillins (class concept)
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21
Q

What is class concept?

A

The test results for sensitivity to one antibiotics applies to all other antibiotics of the same class

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22
Q

How do beta-lactamase resistant penicillins work?

A

“Bulky” side chain added to protect the beta-lactam ring

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23
Q

What penicillins are included in the beta-lactamase resistant class?

A

Oxacillin, cloxacillin, dicloxacillin, methicillin

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24
Q

Is there bacteria resistance to beta-lactamase resistant penicillin? If so, how does it work?

A

Resistance occurs only when the bacteria develops it, by altering their penicillin binding proteins to prevent binding

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25
What is the clinical use of beta-lactamase resistant penicillins?
Orally or injection, use determined by side chain which may alter absorption and excretion
26
What laboratory testing is done on beta-lactamase resistant penicillin in regards to sensitivity?
Class concept applies, oxacillin is usually used
27
What are extended spectrum penicillins?
Addition of NH2 (amine) groups to the side chain of penicillin allows antibiotic to penetrate the lipid layer of gram negative cells Called aminopenicillins
28
What is the spectrum of aminopenicillins?
Broad, but not as effective against gram positive
29
What is the spectrum of beta-lactamase resistant penicillin?
Narrow gram positive, usually for Staphylococcus infections
30
Is there bacteria resistance to extended spectrum penicillin? If so, how does it work?
Susceptible to beta-lactamase
31
What laboratory testing is done on extended spectrum penicillin in regards to sensitivity?
Class concept applies, ampicillin is usually used
32
What are examples of extended spectrum penicillin?
Ampicillin, amoxicillin
33
What are anti-pseudomonal penicillins? Why are they used?
Two groups: 1. carboxy penicillins 2. Ureidopenicillins Used because Pseudomonas and other Enterobacteriaceae produce beta-lactamase
34
What spectrum to anti-pseudomonal penicillins have?
Broad, less effective against gram positives
35
Is there resistance to anti-pseudomonal penicillin? If so, how does it work?
Can be inactivated by beta-lactamase from Staphylococcus
36
What is the clinical use for anti-pseudomonal penicillin?
Used against bacteria that is resistant to other antibiotics, very expensive Usually used with aminoglycosides for Pseudomonas
37
What laboratory testing is done on anti-pseudomonal penicillin in regards to susceptibility?
Class concept does not apply, each antibiotic must be tested
38
What are examples of anti-pseudomonal penicillins? (2 groups)
Carboxypenicillin - carbenicillin, ticaricillin | Ureidopenicillin - azlocillin, mezlocillin, piperacillin
39
What are beta-lactamase inhibitors?
Compounds with weak antibiotic properties but that are able to render some beta-lactamase enzymes useless
40
What are 2 beta-lactamase inhibitors?
Clavulanic acid - amox-clav, ticar-clav | Sulbactam - with ampicillin
41
What are cephalosporins?
Beta-lactam antibiotics produced as fermentation products of fungus
42
How many cephalosporin generations exist?
4
43
How are cephalosporin generations separated?
By antibacterial spectrum
44
What are first generation cephalosporins?
Cephalothin, cefazolin, cephalexin
45
What is the spectrum of first generation cephalosporins?
Broad, most gram positives and moderate gram negatives
46
What is the clinical use of first generation cephalosporins?
Cephalothin and cefazolin injected, cephalexin oral | More expensive than penicillin
47
What laboratory testing is done on first generation cephalosporins in regards to sensitivity?
Class concept generally applies, Cepahlothin usually used
48
What are the second generation cephalosporins?
Cefaclor, cefonicid, cefotiam, cefotetan, cefamandole, ceforanide, cefuroxime, cefoxitin
49
What is the spectrum of second generation cephalosporins?
Broad, increased GNB activity but decreased GP activity | None effective against Pseudomonas
50
What sensitivity testing is done on second generation cephalosporins?
Class concept does not apply, each one must be tested
51
What are the third generation cephalosporins?
Cefixime, cefotaxime, ceftizoxime, cefoperazone, ceftazidime, ceftriaxone
52
What is the spectrum of third generation cephalosporins?
Broad, less against GP, more against Enterobacteriaceae and Pseudomonas
53
What sensitivity testing is done on third generation cephalosporins?
Class concept does not apply, each must be tested
54
What is one clinical use for third generation cephalosporins?
Crosses the blood-brain barrier more easily than first generations
55
What are the fourth generation cephalosporins?
Cefipime, cefpirome
56
What is the spectrum of fourth generation cephalosporins?
Broad
57
What is aztreonam?
Beta-lactam structure with no attachments that disrupts cell wall synthesis the same way penicillin and cephalosporin does
58
What is azteronam used for?
Very effective against Enterobacteriaceae and Pseudomonas that are resistant to other antibiotics, but not GP or anaerobes
59
What are ESBL's?
Extended spectrum beta-lactamases | Enzymes that mediate resistance to extended spectrum cephalosporins (3rd gen)
60
What bacteria can produce ESBL's?
Certain GNs like E. coli, K. pneumoniae and oxytoca
61
What happens if a bacteria is found out to be an ESBL?
All penicillin, cephalosporins, and aztreonam are reported as resistant
62
What is imipenem?
Beta-lactam antibiotic with unique side chain to make it resistant to most beta-lactamase Part of Carbapenem class
63
What is the spectrum of inipenem?
Broad, widest spectrum of any current antibiotic, most GNBs and anaerobes Superbugs are resistant (MRSA, VRE)
64
What is vancomycin?
Belongs to glycopeptide class, not a beta-lactam and does not bind to penicillin binding sites
65
How does vancomycin work?
Binds to precursors of cell wall synthesis
66
What is the spectrum of vancomycin?
Narrow gram positive, large molecule cannot penerate GN cell wall
67
What is the clinical use of vancomycin?
Usually reserved for MRSA, Clostridium difficile, and resistant Enterococcus
68
What are potential side effects of vancomycin?
Toxic, hearing loss
69
What is teicoplanin?
Newer complex glycopeptide with similar spectrum to vancomycin
70
What antibiotics have a cell wall synthesis inhibiting mode of action?
Penicillin, cephalosporins, aztreaonam, imipenem, vancomycin, teicoplanin
71
What is penicillins mode of action?
Cell wall synthesis inhibition
72
What is cephalosporins mode of action?
Cell wall synthesis inhibition
73
What is aztreaonams mode of action?
Cell wall synthesis inhibition
74
What is imipenems mode of action?
Cell wall synthesis inhibition
75
What is vancomycins mode of action?
Cell wall synthesis inhibition
76
What is teicoplanins mode of action?
Cell wall synthesis inhibition
77
All antibiotics whose mode of action is cell wall synthesis inhibition bactericidal or bacteriostatic?
Bactericidal
78
What antimicrobials have a mode of action that inhibits protein synthesis?
Macrolides, chloramphenicol, tetracyclines, and aminoglycosides
79
How to antimicrobials that inhibit protein synthesis work?
Differs between the groups | Most common site of action is where tRNA brings amino acids into place in ribosomes
80
Why are protein synthesis inhibiting antimicrobials not overly toxic?
Human and bacterial ribosomes are slightly different
81
What is erythromycin?
Belongs to Macrolide group, has large ring structure with about 20 carbon molecules and one or more "sugars" attached
82
How does erythromycin work?
Binds to ribosomal subunits and halts addition of amino acids in polypeptide chain causing protein synthesis to stop Bacteriostatic
83
What is the spectrum of erythromycin
Narrow, mostly GP but some GN | Ineffective against Enterobacteriaceae
84
What is the clinical use of erythromycin?
Common in S. pyogenes infection in people with pen allergies, some "exotics": Mycoplasma, Legionella, Chlamydia Absorbed well but too big to cross the blood-brain barrier Orally, esther used to prevent vomitting and destruction
85
What is clindamycin?
Lincosamide antibiotic similar to erythromycin
86
What is the spectrum of clindamycin?
Similar to erythromycin (narrow, GP, some GN)
87
What is the clinical use of clindamycin?
Similar to erythromycin but with better absorption and penetration Good for anaerobes
88
What are some side effects of clindamycin?
Diarrhea in 20% of users and many develop pseudomembranous colitis
89
What is chloramphenicol?
Small molecule made of nitrobenzene ring and small side chain First isolated from Streptomyces in soil
90
How does chloamphenicol work?
Inhibits protein synthesis by binding to ribosomal subunits halting protein synthesis Bacteriostatic
91
What is the spectrum of chloramphenicol?
Broad, GP and Enterobacteriaceae
92
What is the clinical use of chloramphenicol?
Penetrates most body tissue including the blood-brain barrier Toxic, restricted to typhoid and meningitis when other antibiotics cannot penetrate the involved tissues
93
What are the side effects of chloramphenicol in infants? What causes this?
Gray's syndrome - ashen gray cyanosis, weak, listless Chloramphenicol is conjugated in the liver before it is excreted and infant livers cannot convert it to an excretal form, and it builds up in their bodies FATAL
94
What are the side effects in adult patients taking chloramphenicol?
May develop fatal irreversible bone marrow aplasia (aplastic anemia) May cause dose-related bone marrow depression that will go away after discontinuation
95
What is tetracycline?
Has four fused rings and additions of different side chains, yellow colored
96
What are examples of tetracyclines?
Terramycin, aureomycin, doxycycline, minocycline
97
How do tetracyclines work?
Bind to ribosomal subunit preventing binding of tRNA and mRNA which inhibits protein synthesis Bacteriostatic
98
What spectrum do tetracyclines have? Is there any resistance?
Broad, some Enterobacteriaceae | Resistance is common
99
What is the clinical use of tetracyclines?
"Exotics": chlamydia, mycoplasma, rickettsial infections | Orally
100
What are some side effects of tetracyclines?
Yellow teeth from tetracycline deposits Prevents magnesium and calcium absorption, not for child use May interfere with birth control
101
What are aminoglycosides?
Large group of antibiotics sharing same structure of amino sugars liked by glycosidic bonds
102
How do aminoglycosides work?
Inhibit protein synthesis by binding to ribosomal subunit resulting in protein synthesis interruption at several steps Bactericidal
103
What is the clinical use of aminoglycosides?
No good for anaerobes (cannot penetrate in reduced oxygen) Too big to penetrate CNS Often given with beta-lactams, as uptake is facilitated by cell wall inhibitors Also affected by presence of calcium and magnesium
104
What is required for aminoglycoside susceptibility testing?
Media that has the same calcium and magnesium concentration as the body Class concept does not apply, all must be tested
105
What is the spectrum of aminoglycosides?
Broad including Enterobacteriaceae and Pseudomonas
106
What are side effects of aminoglycosides?
Toxicity - kidney | Can damage the eighth cranial nerve and cause hearing loss
107
What are some examples of aminoglycosides?
Kanamycin - for Enterobacteriaceae Gentamicin - for Pseudomonas, in combination with carbenicillin or ticaricillin, resistant Enterobacteriaceae or S. aureus Tobramycin - for Pseudomonas with anti-pseudomonal penicillin Amikacin and netilmicin Spectinomycin - for pen resistant N gonorrhoeae
108
What are fluoroquinolones?
Belong to quinolone class, two ringed structure with different side chains and substitutions including fluorine
109
What are examples of fluoroquinolones?
Ciprofloxacin and norfloxacin
110
What is the mode of action of fluoroquinolones?
Inhibit DNA and RNA synthesis Interfere with DNA gyranase enzymes preventing DNA replication Bactericidal
111
What is the spectrum of fluoroquinolones?
Broad, GP and wide range of GN including Enterobacteriaceae and Pseudomonas
112
What are the side effects of fluoroquinolones?
Toxic, irreversible cartilage and skeletal damage | Not for under 18 year olds or pregnant/nursing mothers
113
What is nalidixic acid?
Belongs to quinolone group
114
What is the spectrum of nalidixic acid?
Broad, GN and Enterococci
115
What is the clinical use of nalidixic acid?
Urinary tract infections, concentrates there | Not effective elsewhere
116
What is the mode of action of metronidazole (flagyl)?
Breaks DNA strands | Bactericidal
117
What is the clinical use of metronidazole (flagyl)?
Anaerobic infections, protazoan parasitic infections like Trichomonas and Giardia
118
What antimicrobials have the mode of actions of inhibiting DNA and RNA synthesis?
Quinolones, fluoroquinolones, nalidixic acid, metronidazole (flagyl)
119
What antimicrobials have the mode of action of inhibiting cell membrane function?
Polymyxins
120
What are polymyxins?
Belong to antibiotic group Polypeptides
121
What is the mode of action of polymyxins?
Inhibit cell membrane function by attaching to the membrane and causing leakage and death Bactericidal
122
What is the spectrum of polymyxins?
Narrow, GN
123
What are examples of polymyxins?
Polymyxin B, Polymyxin E (Colistin)
124
What is the clinical use of polymyxins?
Used to be used for Pseudomonas before more effective and less toxic antibiotics were found
125
What are the side effects of polymyxins?
Toxic | Nephrotoxicity (kidney) and neurotoxicity (nerves)
126
What agar plate and disc is a polymyxin used in? What does it do?
Colistin is used in the CNA plate to inhibit gram negative growth Colistin disc also used to determine gram reaction
127
What antimicrobials have the mode of action of inhibiting other metabolic processes?
Sulfonamides, trimethoprim, nitrofurantoin
128
What is a sulfonamide?
Antimicrobial but not an antibiotic (synthetic) Derivative of small compound called para-aminobenzene sulfonamide, similar structure to DNA precursor para-amino benzoic acid
129
How do sulfonamides work?
Inhibits other metabolic processes by preventing synthesis of folic acid (DNA precursor) Sulfonamide competes for binding enzyme with PABA (similar structure) Competitive inhibition Bacteriostatic
130
What is the spectrum of sulfonamides?
Broad, but many bacteria develop resistance
131
What is the clinical use of sulfonamides?
Some enter the CNS, popular for UTIs | Most effective with trimethoprim = SXT (cortrimoxazole/trimethoprim sulfamethoxazole)
132
What is trimethoprim?
Similar to sulfonamides
133
How does trimethoprim work?
Inhibits other metabolic processes by interfering with folic acid production from PABA by competitive inhibition with another enzyme
134
What is the spectrum of trimethoprim?
Broad
135
What is the clinical use of trimethoprim?
Often used with sulonamide sulfamethoxazole to make cortrimoxazole/SXT Used for UTIs
136
What is nitrofurantoin?
Belongs to synthetic group called nitrofurans
137
What is the mode of action of nitrofurantoin?
Inhibits other metabolic processes by damaging DNA or interfering with enzyme involved in protein translation Not really understood Bactericidal in high concentration, bacteriostatic in low concentration
138
What is the spectrum of nitrofurantoin?
Broad
139
What is the clinical use of nitrofurantoin?
Low blood levels, ineffective for most infections | Concentrated in the urinary system, used for UTIs
140
The following characteristic defines an antimicrobial agent as an antibiotic a. bacteria do not readily develop resistance to it b. all or part of the compound originally produced by a microorganism c. it selectively kills microorganisms without harming host cells d. it is effective against bacteria in low concentrations
b. all of part of the compound originally produced by a microorganism
141
All of the following are criteria making an antibiotic useful clinically except a. unable to penetrate membranes of prokaryotic cells b. soluble in body fluids c. not cause allergic reactions d. bacteria should not readily develop resistance
a. unable to penetrate membranes of prokaryotic cells
142
Which of the following is not a target area of antimicrobial agents a. cell wall b. plasmids c. cell membrane d. protein synthesis
b. plasmids
143
The beta-lactamase resistant penicillin usually used for susceptibility testing is a. ampicillin b. oxacillin c. benzylpenicillin d. ticaricillin
b. oxacillin
144
The following penicillin should be included in the antimicrobial susceptibility test for E. coli (gram negative rod) a. oxacillin b. methicillin c. penicillin G d. ampicillin
d. ampicillin
145
Anti-pseudomonal penicillin are often given with the following type of antibiotic because of synergistic action a. sulfonamides b. trimethoprim c. aminoglycosides d. macrolides
c. aminoglycosides
146
Clavulanic acid and sulbactam are a. beta-lactamase inhibitors b. beta-lactamase antibiotics c. anti-pseudomonal penicillins d. cephalosporins
a. beta-lactamase inhibitors
147
The generation of cephalosporins showing the most activity against gram negative bacteria is a. first b. second c. third
c. third
148
The class concept can be used in susceptibility testing of the following a. first generation cephalosporins b. second generation cephalosporins c. third generation cephalosporins d. all of the above
a. first generation cephalosporins
149
Imipenem is an antibiotic that is effective against a. MRSA b. VRE c. most gram negative rods and anaerobes d. all of the above
c. most gram negative rods and anaerobes
150
The antibiotic associated with aplastic anemia is a. chloramphenicol b. tetracycline c. ciprofloxacin d. nalidixic acid
a. chloramphenicol
151
Tetracycline is not recommended for children because a. toxic levels accumulate because of an immature liver b. it commonly causes pseudomemranous colitis c. bone structure may be altered d. of nephrotoxicity
c. bone structure may be altered
152
Calcium and magnesium ion concentrations should be adjusted in susceptibility test media to correspond to the of body tissues for testing a. tobramycin b. chloramphenicol c. carbenicillin d. norfloxacin
a. tobramycin
153
The following antibiotic is a fluoroquinolone a. kanamycin b. carbenicillin c. ciprofloxacin d. nirtofurantoin
c. ciprofloxacin
154
A limitation on the use of fluoroquinolones is a. severe allergic reactions b. aplastic anemia c. pseudomembranous colitis d. skeletal damage in young people
d. skeletal damage in young people
155
The target site for antimicrobial action of fluoroquinolones is a. cell wall b. DNA synthesis c. protein synthesis d. cell membrane
b. DNA synthesis
156
An antibiotic that is used for treating anaerobic infections and some protozoans is a. griseofulvin b. metronidazole c. nalidixic acid d. trimethoprim
b. metronidazole
157
Co-trimoxazole is a combination of a. carbenicillin and gentamicin b. sulfonamide and trimethoprim c. tetracycline and gentamicin d. sulfonamide and colistin
b. sulfonamide and trimethoprim
158
An antibiotic with a gram negative spectrum that is used in media as a selective agent is a. vancomycin b. trimethoprim c. erythromycin d. colistin
d. colistin
159
An antibiotic that interferes with cell membrane function is a. trimethoprim b. metronidazole c. polymyxin d. erythromycin
c. polymyxin
160
Mycoplasma is bacteria that lack a cell wall. Which of the following antimicrobials would be expected to be effective in treating mycoplasma pneuonia? a. amoxicillin b. erythromycin c. vancomycin d. cephalosporin
b. erythromycin
161
This question may have more than 1 correct answer: The following antimicrobial agents are classed as beta-lactams: a. gentimicin b. cephalosporin c. chloramphenicol d. penicillins
b and d | Cephalosporin and penicillin
162
This question may have more than 1 correct answer: The bacterial cell wall is a suitable target site for antimicrobials because a. antibiotics bind to teichoic acids b. it contains unique polysaccharides c. it contains a unique pohspolipid bilayer d. peptidoglycan of bacterial cell walls is not found in human cells
d. peptidoglycan of bacterial cell wall is not found in human cells
163
This question may have more than 1 correct answer: Anti-pseudomonal penicillins include: a. amikacin b. ureidopenicillins c. tobramycin d. carbenicillin
b and d | Ureidopenicillins and carbenicillin
164
This question may have more than 1 correct answer: Vancomycin: a. inhibits cell wall synthesis b. is a beta-lactam antibiotic c. has a gram positive spectrum d. is bacteriostatic
a and c | Inhibits cell wall synthesis and has a gram positive spectrum
165
This question may have more than 1 correct answer: The following antibiotics inhibit bacterial growth by interfering with protein synthesis: a. macrolides b. tetracycline c. aminoglycosides d. erythromycin
a, b, c, and d | Macrolides, tetracycline, aminoglycosides, and erythromycin
166
This question may have more than 1 correct answer: Erythromycin: a. is effective against Enterobacteriaceae b. is a macrolide c. interferes with folic acid production d. has a gram positive spectrum
b and d | Is a macrolide and has a gram positive spectrum
167
This question may have more than 1 correct answer: The following antibiotics are aminoglycosides: a. tobramycin b. kanamycin c. gentamicin d. aureomycin
a, b, and c | Tobramycin, kanamycin, and gentamicin
168
This question may have more than 1 correct answer: The following statements apply to aminoglycosides a. effective against gram negative rods b. broad spectrum c. inhibit protein synthesis d. class concept applies for susceptibility testing
a, b, and c | Effective against gram negative rods, broad spectrum, and inhibits protein synthesis
169
This question may have more than 1 correct answer: The following antimicrobials are reserved for treating urinary tract infections a. nalidixic acid b. sulfonamides c. nitrofurantoin d. trimethoprim
a, b, c, and d | Nalidixic acid, sulfonamides, nitrofurantoin, and trimethoprim
170
This question may have more than 1 correct answer: Sulfonamides and trimethoprim have the following in common: a. mode of action is competitive inhibition b. broad spectrum c. interfere with production of folic acid from PABA d. interfere with nucleic acid synthesis in humans
a, b, and c | Mode of action is competitive inhibition, broad spectrum, and interfere with production of folic acid from PABA
171
The 4 possible answers are: bactericidal, bacteriostatic, broad spectrum, and narrow spectrum An antibiotic such as penicillin that causes major rupture of predominately gram positive cell walls is:
bactericidal and narrow spectrum
172
The 4 possible answers are: bactericidal, bacteriostatic, broad spectrum, and narrow spectrum A polymyxin that attaches to the cell membrane of gram negative bacteria and causes leakage of contents is:
bactericidal and narrow spectrum
173
The 4 possible answers are: bactericidal, bacteriostatic, broad spectrum, and narrow spectrum A sulfonamide that inhibits formation of folic acid and stops growth of gram positive and negative bacteria is:
bacteriostatic and broad spectrum
174
The 5 possible answers are: Penicillin G, Oxacillin, Methicillin, Ampicillin, and Carbenicillin Beta-lactam antibiotics are:
All of them | Penicillin G, Oxacillin, Methicillin, Ampicillin, and Carbenicillin
175
The 5 possible answers are: Penicillin G, Oxacillin, Methicillin, Ampicillin, and Carbenicillin Natural penicillins are:
Penicillin G
176
The 5 possible answers are: Penicillin G, Oxacillin, Methicillin, Ampicillin, and Carbenicillin Broad spectrum penicillins are:
Ampicillin and Carbenicillin
177
The 5 possible answers are: Penicillin G, Oxacillin, Methicillin, Ampicillin, and Carbenicillin The penicillins used for treatment of Pseudomonas are:
Carbenicillin
178
The 5 possible answers are: Penicillin G, Oxacillin, Methicillin, Ampicillin, and Carbenicillin Benzylpenicillins are:
Penicillin G
179
The 5 possible answers are: Penicillin G, Oxacillin, Methicillin, Ampicillin, and Carbenicillin Penicillins that are activated by the action of beta-lactamase are:
Penicillin G, Ampicillin, and Carbenicillin
180
The 5 possible answers are: Penicillin G, Oxacillin, Methicillin, Ampicillin, and Carbenicillin Class concept applies for susceptibility testing for:
Penicillin G, Oxacillin, Methicillin, and Ampicillin
181
The 5 possible answers are: Penicillin G, Oxacillin, Methicillin, Ampicillin, and Carbenicillin Carboxypenicillins are:
Carbenicillin