What is the first-line treatment for pneumonia in pediatric patients?

First-Line Treatment for Pediatric Pneumonia

Oral amoxicillin 90 mg/kg/day divided into 2 doses is the first-line treatment for children under 5 years with presumed bacterial community-acquired pneumonia, while children 5 years and older should receive the same amoxicillin dose with addition of a macrolide (azithromycin 10 mg/kg day 1, then 5 mg/kg/day for days 2-5) if atypical pathogens cannot be clinically distinguished. 1, 2

Outpatient Treatment Algorithm

Children Under 5 Years

• First-line therapy: Oral amoxicillin 90 mg/kg/day in 2 divided doses (maximum 4 g/day) for 5 days 1, 2
• This dosing provides optimal coverage against Streptococcus pneumoniae and Haemophilus influenzae, the most common bacterial pathogens in this age group 3
• The 5-day course is as effective as 10-day regimens for uncomplicated pneumonia, with moderate certainty of evidence 4

Children 5 Years and Older

• First-line therapy: Oral amoxicillin 90 mg/kg/day in 2 divided doses PLUS azithromycin 1, 2
• Azithromycin dosing: 10 mg/kg on day 1 (maximum 500 mg), followed by 5 mg/kg once daily on days 2-5 (maximum 250 mg/day) 1, 2, 5
• The addition of a macrolide is critical in this age group because Mycoplasma pneumoniae and Chlamydophila pneumoniae become more prevalent 1

Alternative for Presumed Atypical Pneumonia (Any Age)

• Azithromycin monotherapy using the same dosing schedule above can be used when atypical pathogens are strongly suspected 1, 2

Inpatient Treatment Algorithm

Fully Immunized Children with Minimal Local Penicillin Resistance

• First-line therapy: Intravenous ampicillin 150-200 mg/kg/day divided every 6 hours OR penicillin G 200,000-250,000 U/kg/day divided every 4-6 hours 3, 1
• This narrow-spectrum approach is highly effective when local resistance patterns permit 3

Significant Local Penicillin Resistance or Incomplete Immunization

• First-line therapy: Ceftriaxone 50-100 mg/kg/day every 12-24 hours OR cefotaxime 150 mg/kg/day every 8 hours 3, 1
• Third-generation cephalosporins provide enhanced coverage against beta-lactamase-producing H. influenzae and resistant S. pneumoniae 3

Life-Threatening Infection or Empyema

• First-line therapy: Third-generation cephalosporin (ceftriaxone or cefotaxime) at doses above 3
• Vancomycin or clindamycin should be added if methicillin-resistant Staphylococcus aureus is suspected based on local epidemiology 3

Hospitalized Children Requiring Atypical Coverage

• Add azithromycin 10 mg/kg IV once daily (maximum 500 mg) to beta-lactam therapy when M. pneumoniae or C. pneumoniae are significant considerations 3, 1

Second-Line Treatment for Outpatient Failures

If Initial Treatment Was Amoxicillin

• Preferred second-line: High-dose amoxicillin-clavulanate 80-90 mg/kg/day of amoxicillin component in divided doses (maximum 6.4 mg/kg/day clavulanic acid) 3
• This enhances activity against beta-lactamase-producing H. influenzae and resistant S. pneumoniae 3
• Alternative: Oral cephalosporins (cefuroxime, cefpodoxime, cefprozil) provide improved coverage against beta-lactamase producers, though less active than high-dose amoxicillin-clavulanate against S. pneumoniae 3

If Initial Treatment Was Co-trimoxazole

• Preferred second-line: Oral amoxicillin 50 mg/kg in 2 divided doses for 5 days 3

Treatment Duration

• Standard duration: 5 days for uncomplicated pneumonia 1, 2
• Complicated pneumonia: 2-4 weeks may be required 2
• Azithromycin regimens: Always 5 days regardless of severity 1, 5
• Recent evidence demonstrates 5-day amoxicillin courses are equally effective as 10-day regimens for uncomplicated CAP 4

Assessment of Treatment Response

• Expected improvement timeframe: Clinical improvement should occur within 48-72 hours, including resolution of fever and significant reduction in respiratory symptoms 1, 2
• Signs requiring reevaluation: Persistent fever beyond 48-72 hours, worsening respiratory distress, or development of new symptoms 1, 2
• Further investigation needed: Consider alternative diagnoses, resistant pathogens, complications (parapneumonic effusion, empyema), or inadequate drug absorption 1

Special Populations and Critical Considerations

Penicillin Allergy

• Non-severe allergic reactions: Consider oral cephalosporins (cefpodoxime, cefuroxime, cefprozil) under medical supervision 1, 2
• Severe penicillin allergies: Use macrolides, linezolid, or clindamycin 1, 2

HIV-Endemic Areas or Known HIV Infection

• First-line therapy: Amoxicillin regardless of co-trimoxazole prophylaxis status 3
• Refer to hospital if patient fails first-line therapy, as Pneumocystis jirovecii may be involved 3

Malaria-Endemic Regions

• Amoxicillin is preferred over co-trimoxazole because it lacks anti-malarial activity 3
• If malaria cannot be excluded, prescribe both anti-malarial therapy and amoxicillin 3
• Assess for severe anemia (marked pallor of palms, nail beds, conjunctivae) which requires hospital referral 3
• Avoid erythromycin if mefloquine or halofantrine prescribed due to arrhythmia risk 3

Areas Where Referral Is Impossible

• Use injectable agents (ceftriaxone, penicillin/gentamicin, or chloramphenicol) for treatment failures requiring broader coverage 3

Common Pitfalls to Avoid

• Avoid co-trimoxazole or standard macrolides as monotherapy for presumed pneumococcal pneumonia due to high resistance rates 1
• Do not use parenteral ceftriaxone in peripheral outpatient settings in low-resource areas where oral agents are more practical and cost-effective 3
• Do not assume parenteral therapy is superior to oral therapy when oral agents are appropriate—this perception is difficult to correct but not evidence-based 3
• Do not overlook vaccination status—fully immunized children may safely receive narrow-spectrum penicillin/ampicillin rather than broad-spectrum cephalosporins 3, 1
• Avoid unnecessarily broad-spectrum therapy as this drives resistance; narrow-spectrum penicillin or ampicillin is equally effective as cefuroxime for non-complicated CAP in previously healthy children 6