NURS 5334 Advanced Pharmacology
Antimicrobials ACTUAL EXAM |
Comprehensive Practice Exam | Verified
Q&A | Pass Guaranteed - A+ Graded
SECTION 1: PRINCIPLES OF ANTIMICROBIAL THERAPY
(Questions 1-20)
Q1: A patient with sepsis is started on broad-spectrum antibiotics before culture results are
available. Once culture and sensitivity results are received, the antibiotic regimen is changed to a
narrower-spectrum agent based on the specific pathogen. This is known as:
● A. Empiric therapy
● B. Definitive therapy [CORRECT]
● C. Prophylactic therapy
● D. Suppressive therapy
Correct Answer: B
Rationale: Definitive therapy is treatment based on culture and sensitivity results targeting the
specific identified pathogen. Empiric therapy (A) is the initial broad-spectrum treatment started
before culture results are available. Prophylactic therapy (C) prevents infection in high-risk
situations (surgery, immunocompromised patients). Suppressive therapy (D) prevents recurrence
,of infection. The transition from broad to narrow spectrum is a key antimicrobial stewardship
principle.
NURS 5334 Note: Always de-escalate to definitive therapy once culture results return to reduce
resistance and adverse effects.
Q2: Which characteristic best describes concentration-dependent killing antibiotics?
● A. Efficacy is related to time above MIC
● B. Efficacy is related to peak concentration [CORRECT]
● C. They have no post-antibiotic effect
● D. They require continuous infusion for optimal effect
Correct Answer: B
Rationale: Concentration-dependent killing antibiotics (aminoglycosides, fluoroquinolones,
metronidazole) demonstrate increased bacterial killing with higher peak concentrations. The
AUC/MIC or Cmax/MIC ratio predicts efficacy. Time-dependent killers (beta-lactams, vancomycin,
macrolides) require time above MIC for efficacy (A). Concentration-dependent antibiotics typically
have significant post-antibiotic effects (PAE) (C), allowing once-daily dosing rather than continuous
infusion (D).
Q3: A 68-year-old patient with endocarditis caused by Enterococcus faecalis is treated with
ampicillin plus gentamicin. This combination represents:
● A. Antagonism
● B. Synergism [CORRECT]
● C. Additive effect
● D. Indifference
,Correct Answer: B
Rationale: Beta-lactam (ampicillin) plus aminoglycoside (gentamicin) combinations demonstrate
synergism against enterococci. The beta-lactam enhances aminoglycoside uptake by disrupting
cell wall synthesis. This combination is bactericidal against enterococci (neither agent alone is
reliably bactericidal against E. faecalis). Synergism produces an effect greater than the sum of
individual effects. Antagonism (A) occurs when combining bacteriostatic and bactericidal agents.
NURS 5334 Note: Synergy is crucial for enterococcal endocarditis, prosthetic valve infections, and
some gram-negative infections.
Q4: Which antibiotic exhibits time-dependent killing with minimal post-antibiotic effect?
● A. Ciprofloxacin
● B. Gentamicin
● C. Piperacillin [CORRECT]
● D. Metronidazole
Correct Answer: C
Rationale: Piperacillin (beta-lactam) exhibits time-dependent killing where efficacy depends on the
percentage of time that free drug concentrations exceed the MIC (%fT>MIC). Beta-lactams have
minimal PAE against most organisms. Ciprofloxacin (A), gentamicin (B), and metronidazole (D) are
concentration-dependent killers with significant PAE.
Q5: Therapeutic drug monitoring (TDM) is routinely required for which antibiotic in a patient with
normal renal function?
● A. Ceftriaxone
, ● B. Azithromycin
● C. Vancomycin [CORRECT]
● D. Metronidazole
Correct Answer: C
Rationale: Vancomycin requires TDM (trough monitoring) to ensure efficacy (trough 10-20 mcg/mL
for most infections; 15-20 mcg/mL for serious infections like pneumonia, endocarditis,
osteomyelitis) and minimize nephrotoxicity. Aminoglycosides also require TDM. Beta-lactams (A),
macrolides (B), and metronidazole (D) have wide therapeutic indices and do not require routine
TDM in patients with normal organ function.
Q6: The minimum inhibitory concentration (MIC) is defined as:
● A. The lowest concentration that kills 99.9% of bacteria
● B. The lowest concentration that inhibits visible bacterial growth [CORRECT]
● C. The concentration that prevents resistance development
● D. The concentration that produces therapeutic drug levels
Correct Answer: B
Rationale: MIC is the lowest concentration of an antibiotic that inhibits visible bacterial growth after
18-24 hours of incubation. It measures bacteriostatic activity. The minimum bactericidal
concentration (MBC) (A) is the lowest concentration that kills 99.9% of bacteria. Lower MIC values
indicate greater bacterial susceptibility.
Q7: A patient requires antibiotic prophylaxis before orthopedic surgery. Which principle guides
appropriate prophylactic therapy?
● A. Continue antibiotics for 7 days postoperatively
Antimicrobials ACTUAL EXAM |
Comprehensive Practice Exam | Verified
Q&A | Pass Guaranteed - A+ Graded
SECTION 1: PRINCIPLES OF ANTIMICROBIAL THERAPY
(Questions 1-20)
Q1: A patient with sepsis is started on broad-spectrum antibiotics before culture results are
available. Once culture and sensitivity results are received, the antibiotic regimen is changed to a
narrower-spectrum agent based on the specific pathogen. This is known as:
● A. Empiric therapy
● B. Definitive therapy [CORRECT]
● C. Prophylactic therapy
● D. Suppressive therapy
Correct Answer: B
Rationale: Definitive therapy is treatment based on culture and sensitivity results targeting the
specific identified pathogen. Empiric therapy (A) is the initial broad-spectrum treatment started
before culture results are available. Prophylactic therapy (C) prevents infection in high-risk
situations (surgery, immunocompromised patients). Suppressive therapy (D) prevents recurrence
,of infection. The transition from broad to narrow spectrum is a key antimicrobial stewardship
principle.
NURS 5334 Note: Always de-escalate to definitive therapy once culture results return to reduce
resistance and adverse effects.
Q2: Which characteristic best describes concentration-dependent killing antibiotics?
● A. Efficacy is related to time above MIC
● B. Efficacy is related to peak concentration [CORRECT]
● C. They have no post-antibiotic effect
● D. They require continuous infusion for optimal effect
Correct Answer: B
Rationale: Concentration-dependent killing antibiotics (aminoglycosides, fluoroquinolones,
metronidazole) demonstrate increased bacterial killing with higher peak concentrations. The
AUC/MIC or Cmax/MIC ratio predicts efficacy. Time-dependent killers (beta-lactams, vancomycin,
macrolides) require time above MIC for efficacy (A). Concentration-dependent antibiotics typically
have significant post-antibiotic effects (PAE) (C), allowing once-daily dosing rather than continuous
infusion (D).
Q3: A 68-year-old patient with endocarditis caused by Enterococcus faecalis is treated with
ampicillin plus gentamicin. This combination represents:
● A. Antagonism
● B. Synergism [CORRECT]
● C. Additive effect
● D. Indifference
,Correct Answer: B
Rationale: Beta-lactam (ampicillin) plus aminoglycoside (gentamicin) combinations demonstrate
synergism against enterococci. The beta-lactam enhances aminoglycoside uptake by disrupting
cell wall synthesis. This combination is bactericidal against enterococci (neither agent alone is
reliably bactericidal against E. faecalis). Synergism produces an effect greater than the sum of
individual effects. Antagonism (A) occurs when combining bacteriostatic and bactericidal agents.
NURS 5334 Note: Synergy is crucial for enterococcal endocarditis, prosthetic valve infections, and
some gram-negative infections.
Q4: Which antibiotic exhibits time-dependent killing with minimal post-antibiotic effect?
● A. Ciprofloxacin
● B. Gentamicin
● C. Piperacillin [CORRECT]
● D. Metronidazole
Correct Answer: C
Rationale: Piperacillin (beta-lactam) exhibits time-dependent killing where efficacy depends on the
percentage of time that free drug concentrations exceed the MIC (%fT>MIC). Beta-lactams have
minimal PAE against most organisms. Ciprofloxacin (A), gentamicin (B), and metronidazole (D) are
concentration-dependent killers with significant PAE.
Q5: Therapeutic drug monitoring (TDM) is routinely required for which antibiotic in a patient with
normal renal function?
● A. Ceftriaxone
, ● B. Azithromycin
● C. Vancomycin [CORRECT]
● D. Metronidazole
Correct Answer: C
Rationale: Vancomycin requires TDM (trough monitoring) to ensure efficacy (trough 10-20 mcg/mL
for most infections; 15-20 mcg/mL for serious infections like pneumonia, endocarditis,
osteomyelitis) and minimize nephrotoxicity. Aminoglycosides also require TDM. Beta-lactams (A),
macrolides (B), and metronidazole (D) have wide therapeutic indices and do not require routine
TDM in patients with normal organ function.
Q6: The minimum inhibitory concentration (MIC) is defined as:
● A. The lowest concentration that kills 99.9% of bacteria
● B. The lowest concentration that inhibits visible bacterial growth [CORRECT]
● C. The concentration that prevents resistance development
● D. The concentration that produces therapeutic drug levels
Correct Answer: B
Rationale: MIC is the lowest concentration of an antibiotic that inhibits visible bacterial growth after
18-24 hours of incubation. It measures bacteriostatic activity. The minimum bactericidal
concentration (MBC) (A) is the lowest concentration that kills 99.9% of bacteria. Lower MIC values
indicate greater bacterial susceptibility.
Q7: A patient requires antibiotic prophylaxis before orthopedic surgery. Which principle guides
appropriate prophylactic therapy?
● A. Continue antibiotics for 7 days postoperatively
