NURS 5334 Antimicrobials | Questions
with Detailed Solutions & Rationales |
Comprehensive Exam Graded A+
NURS 5334 Antimicrobials:
1. Penicillin MOA
Correct Ans>>>- Beta-lactam antibiotics weaken the cell wall, causing bacteria to
take up excessive amounts of water and rupture. They are bactericidal.
2. How microbes resist drugs
Correct Ans>>>- (1) decrease the concentration of a drug at its site of action, (2)
alter the structure of drug target molecules, (3) produce a drug antagonist, and
(4) cause drug inactivation.
3. How do antibiotics promote resistance?
Correct Ans>>>- (1) microbes secrete compounds that are toxic to other
microbes, and (2) microbes within a given ecologic location compete with each
other for available nutrients. Under drug-free conditions, the various microbes
keep each other in check. If a drug-resistant organism is present, antibiotics will
create selection pressure favoring its growth by killing off sensitive organisms.
4. Which antibiotics promote resistance?
Correct Ans>>>- All antimicrobial drugs promote the emergence of drug-resistant
organisms. Broad-spectrum antibiotics kill more competing organisms than do
narrow-spectrum drugs, therefore broad-spectrum agents do the most to
facilitate emergence of resistance.
5. What is conjugation?
Correct Ans>>>- Conjugation is a process by which extrachromosomal DNA is
transferred from one bacterium to another.
6. What does the NDM-1 gene do?
Correct Ans>>>- Extensive drug resistance is conferred by the NDM-1 gene, which
codes for a powerful form of β-lactamase. It can inactivate essentially all β-lactam
antibiotics, a group that includes penicillins, cephalosporins, and carbapenems.
,7. Bacterial resistance to penicillin
Correct Ans>>>- (1) inability of penicillins to reach their targets (PBPs), (2)
inactivation of penicillins by bacterial enzymes, and (3) production of PBPs that
have a low affinity for penicillins.
8. Penicillin G Activity
Correct Ans>>>- Penicillin G is active against most gram-positive bacteria (except
penicillinase-producing staphylococci), gram-negative cocci (Neisseria
meningitidis and non-penicillinase-producing strains of Neisseria gonorrhoeae),
anaerobic bacteria, and spirochetes (including Treponema pallidum). With few
exceptions, gram-negative bacilli are resistant.
9. Penicillin G
Correct Ans>>>- narrow spectrum penicillin, least toxic antibiotic, given IV or IM.
Procaine Penicillin G can cause behavioral effects. Potassium Penicillin G may
cause hyperkalemia.
10. Patients who have a penicillin allergy might have a cross-allergy to?
Correct Ans>>>- Cephalosporins
11. Penicillin immediate reaction
Correct Ans>>>- occur 2 to 30 minutes after drug administration, mediated by
immunoglobulin E (IgE) antibodies.
12. Penicillin accelerated reaction
Correct Ans>>>- accelerated reactions occur within 1 to 72 hours, mediated by
immunoglobulin E (IgE) antibodies.
13. Penicillin delayed reaction
Correct Ans>>>- reactions occur within days to weeks.
14. Penicillin V aka VK
Correct Ans>>>- penicillin V has replaced penicillin G for oral therapy. Penicillin V
may be taken with meals. Narrow spectrum.
15. narrow-spectrum penicillins that are penicillinase resistant
(antistaphylococcal penicillins)
Correct Ans>>>- nafcillin, oxacillin, and dicloxacillin. Group of penicillins that are
highly resistant to inactivation by β-lactamases.
, 16. Broad-spectrum penicillins
Correct Ans>>>- Ampicillin and amoxicillin. Active against gram-positive bacteria
and a significant number of gram-negative bacteria. They are not resistant to
penicillinase.
17. Antipseudomonal penicillins
Correct Ans>>>- Piperacillin and ticarcillin. Often combined with a beta-lactamase
inhibitor like tazobactam or clavulanic acid to extend their spectrum.
18. Beta-lactamase inhibitors
Correct Ans>>>- Clavulanic acid, sulbactam, and tazobactam. They lack significant
antibacterial activity but inhibit beta-lactamases, protecting penicillins that are
susceptible to degradation.
19. Amoxicillin-clavulanate (Augmentin) is used for
Correct Ans>>>- Otitis media, sinusitis, and animal bites due to its activity against
beta-lactamase-producing organisms like Staphylococcus aureus and
Haemophilus influenzae.
20. Ampicillin is the drug of choice for
Correct Ans>>>- Listeria monocytogenes and Enterococcus faecalis. It is also used
for Shigella and Salmonella infections.
21. Nafcillin clinical use
Correct Ans>>>- Treatment of methicillin-susceptible Staphylococcus
aureus (MSSA) infections. Not used for MRSA.
22. Most common adverse effect of penicillins
Correct Ans>>>- Hypersensitivity reactions, ranging from rash to anaphylaxis.
23. Methicillin
Correct Ans>>>- An antistaphylococcal penicillin no longer used clinically due to
high risk of interstitial nephritis.
24. Cephalosporin MOA
Correct Ans>>>- Beta-lactam antibiotics that inhibit bacterial cell wall synthesis,
leading to cell lysis. They are bactericidal.
25. First-generation cephalosporin
Correct Ans>>>- Cefazolin (IV) and cephalexin (oral). Excellent activity against
with Detailed Solutions & Rationales |
Comprehensive Exam Graded A+
NURS 5334 Antimicrobials:
1. Penicillin MOA
Correct Ans>>>- Beta-lactam antibiotics weaken the cell wall, causing bacteria to
take up excessive amounts of water and rupture. They are bactericidal.
2. How microbes resist drugs
Correct Ans>>>- (1) decrease the concentration of a drug at its site of action, (2)
alter the structure of drug target molecules, (3) produce a drug antagonist, and
(4) cause drug inactivation.
3. How do antibiotics promote resistance?
Correct Ans>>>- (1) microbes secrete compounds that are toxic to other
microbes, and (2) microbes within a given ecologic location compete with each
other for available nutrients. Under drug-free conditions, the various microbes
keep each other in check. If a drug-resistant organism is present, antibiotics will
create selection pressure favoring its growth by killing off sensitive organisms.
4. Which antibiotics promote resistance?
Correct Ans>>>- All antimicrobial drugs promote the emergence of drug-resistant
organisms. Broad-spectrum antibiotics kill more competing organisms than do
narrow-spectrum drugs, therefore broad-spectrum agents do the most to
facilitate emergence of resistance.
5. What is conjugation?
Correct Ans>>>- Conjugation is a process by which extrachromosomal DNA is
transferred from one bacterium to another.
6. What does the NDM-1 gene do?
Correct Ans>>>- Extensive drug resistance is conferred by the NDM-1 gene, which
codes for a powerful form of β-lactamase. It can inactivate essentially all β-lactam
antibiotics, a group that includes penicillins, cephalosporins, and carbapenems.
,7. Bacterial resistance to penicillin
Correct Ans>>>- (1) inability of penicillins to reach their targets (PBPs), (2)
inactivation of penicillins by bacterial enzymes, and (3) production of PBPs that
have a low affinity for penicillins.
8. Penicillin G Activity
Correct Ans>>>- Penicillin G is active against most gram-positive bacteria (except
penicillinase-producing staphylococci), gram-negative cocci (Neisseria
meningitidis and non-penicillinase-producing strains of Neisseria gonorrhoeae),
anaerobic bacteria, and spirochetes (including Treponema pallidum). With few
exceptions, gram-negative bacilli are resistant.
9. Penicillin G
Correct Ans>>>- narrow spectrum penicillin, least toxic antibiotic, given IV or IM.
Procaine Penicillin G can cause behavioral effects. Potassium Penicillin G may
cause hyperkalemia.
10. Patients who have a penicillin allergy might have a cross-allergy to?
Correct Ans>>>- Cephalosporins
11. Penicillin immediate reaction
Correct Ans>>>- occur 2 to 30 minutes after drug administration, mediated by
immunoglobulin E (IgE) antibodies.
12. Penicillin accelerated reaction
Correct Ans>>>- accelerated reactions occur within 1 to 72 hours, mediated by
immunoglobulin E (IgE) antibodies.
13. Penicillin delayed reaction
Correct Ans>>>- reactions occur within days to weeks.
14. Penicillin V aka VK
Correct Ans>>>- penicillin V has replaced penicillin G for oral therapy. Penicillin V
may be taken with meals. Narrow spectrum.
15. narrow-spectrum penicillins that are penicillinase resistant
(antistaphylococcal penicillins)
Correct Ans>>>- nafcillin, oxacillin, and dicloxacillin. Group of penicillins that are
highly resistant to inactivation by β-lactamases.
, 16. Broad-spectrum penicillins
Correct Ans>>>- Ampicillin and amoxicillin. Active against gram-positive bacteria
and a significant number of gram-negative bacteria. They are not resistant to
penicillinase.
17. Antipseudomonal penicillins
Correct Ans>>>- Piperacillin and ticarcillin. Often combined with a beta-lactamase
inhibitor like tazobactam or clavulanic acid to extend their spectrum.
18. Beta-lactamase inhibitors
Correct Ans>>>- Clavulanic acid, sulbactam, and tazobactam. They lack significant
antibacterial activity but inhibit beta-lactamases, protecting penicillins that are
susceptible to degradation.
19. Amoxicillin-clavulanate (Augmentin) is used for
Correct Ans>>>- Otitis media, sinusitis, and animal bites due to its activity against
beta-lactamase-producing organisms like Staphylococcus aureus and
Haemophilus influenzae.
20. Ampicillin is the drug of choice for
Correct Ans>>>- Listeria monocytogenes and Enterococcus faecalis. It is also used
for Shigella and Salmonella infections.
21. Nafcillin clinical use
Correct Ans>>>- Treatment of methicillin-susceptible Staphylococcus
aureus (MSSA) infections. Not used for MRSA.
22. Most common adverse effect of penicillins
Correct Ans>>>- Hypersensitivity reactions, ranging from rash to anaphylaxis.
23. Methicillin
Correct Ans>>>- An antistaphylococcal penicillin no longer used clinically due to
high risk of interstitial nephritis.
24. Cephalosporin MOA
Correct Ans>>>- Beta-lactam antibiotics that inhibit bacterial cell wall synthesis,
leading to cell lysis. They are bactericidal.
25. First-generation cephalosporin
Correct Ans>>>- Cefazolin (IV) and cephalexin (oral). Excellent activity against
