What is the recommended treatment for a previously healthy pediatric patient with community-acquired pneumonia (CAP)?

Treatment of Pediatric Community-Acquired Pneumonia

For previously healthy children with community-acquired pneumonia (CAP), high-dose oral amoxicillin at 90 mg/kg/day divided into 2 doses is the first-line treatment for outpatient management, with a treatment duration of 5-7 days. 1, 2, 3

Outpatient Management Algorithm

First-Line Antibiotic Selection

For fully immunized children (completed Hib and pneumococcal vaccines):

• Amoxicillin 90 mg/kg/day divided into 2 doses (maximum 4 g/day) 1, 2, 3
• This high-dose regimen provides adequate coverage against penicillin-resistant Streptococcus pneumoniae, the most common bacterial pathogen 2, 3
• The 2-dose daily schedule (rather than 3 doses) improves adherence while maintaining efficacy 4

For incompletely immunized children:

• Amoxicillin-clavulanate (Augmentin) 90 mg/kg/day of the amoxicillin component divided into 2 doses 2, 4
• This provides coverage for β-lactamase-producing Haemophilus influenzae 2
• Alternative: Second- or third-generation cephalosporins (cefpodoxime, cefuroxime, cefprozil) 1, 4

Age-Specific Considerations for Atypical Pathogens

Children under 5 years:

• Amoxicillin monotherapy is appropriate 3, 5
• Macrolides should NOT be used as monotherapy due to inadequate pneumococcal coverage 3

Children 5 years and older:

• Start with amoxicillin 90 mg/kg/day 3, 5
• Add a macrolide (azithromycin 10 mg/kg day 1, then 5 mg/kg/day for days 2-5) if symptoms persist after 48-72 hours of β-lactam therapy and atypical pneumonia (Mycoplasma pneumoniae, Chlamydophila pneumoniae) is suspected 1, 5, 6
• This approach is preferred over empiric combination therapy from the start 5, 4

Treatment Duration

5-7 days is the recommended duration for uncomplicated CAP 3, 4, 7, 8

• Recent high-quality evidence demonstrates that 5-day courses are non-inferior to 10-day courses for clinical cure rates 7, 8
• The 2021 CAP-IT trial (824 children) showed no difference in retreatment rates between 3-day and 7-day courses, though cough resolved slightly faster with 7 days 7
• A 2022 meta-analysis confirmed 5-day Amoxicillin regimens are as effective as 10-day regimens 8

Inpatient Management Algorithm

Indications for Hospitalization

Admit children with any of the following:

• Oxygen saturation <92% on room air 3
• Respiratory rate >70 breaths/min in infants 3
• Severe respiratory distress (retractions, grunting, nasal flaring) 3
• Inability to tolerate oral intake or dehydration 3
• Toxic appearance or altered mental status 3

Parenteral Antibiotic Selection

For fully immunized children in areas with minimal penicillin resistance:

• Ampicillin 150-200 mg/kg/day IV every 6 hours (preferred) 1, 3, 5
• Alternative: Penicillin G 200,000-250,000 U/kg/day IV every 4-6 hours 1

For incompletely immunized children OR areas with high penicillin resistance:

• Ceftriaxone 50-100 mg/kg/day IV every 12-24 hours (preferred for once-daily dosing) 1, 5
• Alternative: Cefotaxime 150 mg/kg/day IV every 8 hours 1, 5

If community-acquired MRSA is suspected (empyema, necrotizing pneumonia, severe illness):

• Add vancomycin 40-60 mg/kg/day IV every 6-8 hours OR clindamycin 40 mg/kg/day IV every 6-8 hours (based on local susceptibility) 1

If atypical pneumonia is suspected in hospitalized children:

• Add azithromycin 10 mg/kg IV on day 1 (maximum 500 mg), then 5 mg/kg IV daily (maximum 250 mg) 5, 6

Transition to Oral Therapy

Switch from IV to oral antibiotics when ALL of the following criteria are met:

• Afebrile for 24 hours 3
• Improved respiratory rate and work of breathing 3
• Tolerating oral intake without vomiting 3
• Oxygen saturation stable on room air 3

This typically occurs within 48-72 hours of admission 3, 5

Oral step-down options:

• Amoxicillin 90 mg/kg/day divided into 2 doses 1, 2
• Complete a total antibiotic course of 7 days (IV + oral combined) 3, 5

Monitoring and Reassessment

Expected Clinical Response

Children on appropriate therapy should demonstrate improvement within 48-72 hours, including: 2, 3, 5

• Defervescence (fever resolution) 3, 5
• Decreased respiratory rate 3
• Reduced work of breathing 3
• Improved oral intake 3

Failure to Improve

If no improvement or clinical deterioration occurs by 48-72 hours, investigate for: 3, 5

• Inadequate antibiotic dosing or inappropriate drug selection 3
• Resistant organisms (obtain blood culture, consider sputum culture if feasible) 3
• Complications: parapneumonic effusion, empyema, lung abscess 5
• Alternative diagnoses: viral pneumonia, tuberculosis, foreign body aspiration 5
• Atypical pathogens requiring macrolide therapy 5

Management of treatment failure:

• Obtain chest radiograph to assess for complications 3
• Consider adding or switching to broader spectrum coverage 3, 9
• For hospitalized children who fail narrow-spectrum therapy, broad-spectrum antibiotics (ceftriaxone, amoxicillin-clavulanate) show better outcomes with shorter hospital stays 9

Common Pitfalls and Caveats

Penicillin Allergy

For non-anaphylactic penicillin allergy:

• Use oral cephalosporins (cefpodoxime, cefuroxime, cefprozil) under medical supervision 1, 5

For Type I hypersensitivity (anaphylaxis):

• Use macrolides (azithromycin or clarithromycin) 5
• Alternative: Levofloxacin 16-20 mg/kg/day in 2 doses for children 6 months-5 years; 8-10 mg/kg/day once daily for children 5-16 years (maximum 750 mg/day) 1
• Alternative: Linezolid 30 mg/kg/day in 3 doses for children <12 years; 20 mg/kg/day in 2 doses for children ≥12 years 1

Avoid These Common Errors

• Do not use macrolides as monotherapy in children under 5 years due to high pneumococcal resistance rates and inadequate coverage 3, 5
• Do not use trimethoprim-sulfamethoxazole for presumed pneumococcal pneumonia due to high resistance rates 5
• Do not routinely obtain chest radiographs for uncomplicated outpatient CAP, as clinical diagnosis is sufficient 3
• Do not prescribe 10-day courses when 5-7 days is adequate, as this increases antibiotic exposure without improving outcomes 7, 8

Special Populations

Children with recent antibiotic exposure (within 3 months):

• Use high-dose amoxicillin-clavulanate 90 mg/kg/day of amoxicillin component to cover β-lactamase-producing organisms 2

Children with recurrent pneumonia:

• After acute illness resolves, investigate for underlying conditions: immunodeficiency, anatomic abnormalities (tracheoesophageal fistula, bronchiectasis), aspiration risk, cystic fibrosis 3