What is the recommended treatment for community-acquired pneumonia (CAP)?

Treatment of Community-Acquired Pneumonia (CAP)

For community-acquired pneumonia, the recommended first-line treatment is either a beta-lactam plus macrolide combination or respiratory fluoroquinolone monotherapy, with treatment stratified based on outpatient versus inpatient setting and patient risk factors. 1

Outpatient Treatment

For patients with no comorbidities:

• First-line options:
  • Macrolide monotherapy: Azithromycin 500mg on day 1, followed by 250mg daily for days 2-5 1, 2
  • Doxycycline 100mg twice daily 1

For patients with comorbidities or recent antibiotic use:

• Preferred options:
  • Respiratory fluoroquinolone: Levofloxacin 750mg daily or moxifloxacin 400mg daily 3, 1
  • Beta-lactam plus macrolide: Amoxicillin 1g every 8 hours plus azithromycin (dosing as above) 1

Important note: In regions with high rates (>25%) of macrolide-resistant S. pneumoniae, macrolide monotherapy should be avoided 1

Inpatient Treatment

For hospitalized non-ICU patients:

• Strong recommendations (high quality evidence): 3
  • Beta-lactam (ampicillin-sulbactam 1.5-3g every 6h, cefotaxime 1-2g every 8h, ceftriaxone 1-2g daily, or ceftaroline 600mg every 12h) plus a macrolide (azithromycin 500mg daily or clarithromycin 500mg twice daily)
  • OR respiratory fluoroquinolone monotherapy (levofloxacin 750mg daily or moxifloxacin 400mg daily)

Alternative for patients with contraindications to both macrolides and fluoroquinolones:

• Beta-lactam (as above) plus doxycycline 100mg twice daily (conditional recommendation, low quality evidence) 3

Special Considerations

Treatment Duration:

• Minimum duration of 5 days 1
• Patient should be afebrile for 48-72 hours and have no more than one sign of clinical instability before discontinuation 1

Antibiotic Selection Principles:

1. If a patient has had recent exposure to one class of antibiotics, use a different class for empiric therapy due to increased resistance risk 3, 1
2. For penicillin-allergic patients, respiratory fluoroquinolones are recommended 1
3. First antibiotic dose should be administered while the patient is still in the emergency department for hospitalized patients 1

Pathogen Coverage:

• Treatment should cover both typical bacterial pathogens (particularly S. pneumoniae) and atypical pathogens (Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila) 1, 4
• The most recent evidence indicates that up to 40% of hospitalized CAP cases with identified pathogens are viral, with S. pneumoniae identified in approximately 15% of cases with known etiology 4

Clinical Response Assessment:

• Evaluate response at 48-72 hours, including temperature, WBC, chest X-ray, oxygenation, sputum production, and hemodynamic status 1
• Patients can switch to oral antibiotics when hemodynamically stable, clinically improving, able to take oral medications, and have a normally functioning GI tract 1

Discharge Criteria

• Clinical stability
• No other active medical problems requiring hospitalization
• Safe environment for continued care
• Ability to tolerate oral medication 1

Common Pitfalls to Avoid

1. Underestimating macrolide resistance: In areas with high S. pneumoniae resistance to macrolides, avoid macrolide monotherapy
2. Failing to consider recent antibiotic exposure: Always use a different class of antibiotics if the patient has recently received antibiotics
3. Delaying first antibiotic dose: For hospitalized patients, administer the first dose while still in the emergency department
4. Inadequate duration: Ensure minimum 5-day treatment with clinical stability for 48-72 hours before discontinuation
5. Overlooking COVID-19 and influenza testing: All CAP patients should be tested when these viruses are circulating in the community 4

By following these evidence-based recommendations, clinicians can optimize outcomes for patients with community-acquired pneumonia while minimizing antibiotic resistance and adverse effects.