Examkin

Question

Difficulty: MediumInfectious Diseases

A 68-year-old man is evaluated on hospital day 3 for management of community-acquired pneumonia. He was admitted with a 3-day history of productive cough, fever, and shortness of breath. On admission, chest radiography revealed a left lower lobe infiltrate. He was started on empiric intravenous ceftriaxone and intravenous azithromycin. Today, his cough and shortness of breath have significantly improved. He is tolerating a regular diet well. His temperature is 37.1∘C37.1^{\circ}\text{C} (98.8∘F98.8^{\circ}\text{F}), blood pressure is 128/82 mm Hg128/82\text{ mm Hg}, pulse is 78/min78/\text{min}, and respiratory rate is 16/min16/\text{min}. Oxygen saturation is 96%96\% on ambient air. A sputum culture obtained on admission grew *Streptococcus pneumoniae*. Antimicrobial susceptibility testing demonstrates that the isolate is susceptible to penicillin, amoxicillin, ceftriaxone, and levofloxacin, but resistant to azithromycin. Which of the following is the most appropriate next step in antimicrobial therapy?

  1. Discontinue current antibiotics and begin oral amoxicillinAnswer
  2. B
    Discontinue current antibiotics and begin oral amoxicillin-clavulanate
  3. C
    Discontinue current antibiotics and begin oral levofloxacin
  4. D
    Discontinue azithromycin and continue intravenous ceftriaxone
  5. E
    Continue intravenous ceftriaxone and intravenous azithromycin

Answer

Discontinue the current intravenous antibiotics and transition the patient to oral amoxicillin.
The correct answer transitions the patient to oral amoxicillin. This patient was admitted with community-acquired pneumonia (CAP) and empirically treated with a standard regimen of intravenous ceftriaxone and azithromycin. On hospital day 3, he is clinically stable (afebrile, normal vital signs) and tolerating an oral diet, meaning he is ready to step down to oral therapy. The sputum culture grew Streptococcus pneumoniae susceptible to penicillin and amoxicillin. In accordance with antimicrobial stewardship principles, empiric broad-spectrum therapy should be de-escalated to the narrowest effective agent. Oral amoxicillin provides excellent bioavailability and targeted coverage for susceptible S. pneumoniae, making it the most appropriate choice.

Step-by-Step Solution

1
Evaluate the patient's clinical stability and ability to take oral medications.
The patient is afebrile, hemodynamically stable, and tolerating a regular diet.
Clinical stability dictates the appropriateness of transitioning from intravenous to oral therapy to reduce hospital length of stay and line-associated complications.
2
Analyze the sputum culture and susceptibility results.
The pathogen is Streptococcus pneumoniae, which is susceptible to narrow-spectrum beta-lactams including amoxicillin.
Culture data should guide the de-escalation of empiric broad-spectrum therapy to targeted, pathogen-specific therapy.
3
Select the most appropriate targeted oral agent.
Oral amoxicillin is selected.
Amoxicillin is a highly effective, narrow-spectrum agent for susceptible S. pneumoniae, aligning perfectly with the core principles of antimicrobial stewardship.

Key Concept

Antimicrobial stewardship in community-acquired pneumonia involves transitioning from empiric intravenous therapy to targeted oral therapy once the patient is clinically stable and culture data is available.
Estimated Time:1m 15s
Rate this question

Topics

Infectious Diseases

More questions from this topic