Treatment for a 2-Year-Old with Bacterial Pneumonia (19.6 lbs/8.9 kg)
Give oral amoxicillin 90 mg/kg/day divided into 2 doses daily, which equals approximately 400 mg twice daily (800 mg total per day) for this 8.9 kg child. 1, 2, 3
Dosing Calculation and Administration
- Weight conversion: 19.6 lbs = 8.9 kg
- Recommended dose: 90 mg/kg/day in 2 divided doses 1, 2
- Total daily dose: 8.9 kg × 90 mg/kg = 801 mg/day
- Individual dose: Approximately 400 mg twice daily 1
- Amoxicillin can be given with or without food 1
Rationale for High-Dose Amoxicillin
For children under 5 years old with presumed bacterial pneumonia, high-dose amoxicillin (90 mg/kg/day) is the first-line treatment recommended by the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America. 1, 2, 3 This higher dosing (compared to standard 40-45 mg/kg/day) is critical to overcome potential penicillin-resistant Streptococcus pneumoniae, the most common bacterial cause of community-acquired pneumonia in this age group. 2
When to Consider Alternative or Additional Therapy
If atypical pneumonia is suspected (gradual onset, prominent cough, minimal fever, interstitial infiltrates on chest X-ray):
- Add azithromycin 10 mg/kg on day 1 (approximately 89 mg), followed by 5 mg/kg/day (approximately 45 mg) once daily on days 2-5 1, 2, 4
If community-associated MRSA is suspected (severe illness, necrotizing pneumonia, empyema, recent influenza):
- Add clindamycin 30-40 mg/kg/day divided into 3-4 doses (approximately 267-356 mg/day total, or 67-89 mg per dose if given 4 times daily) 1, 5
Critical Monitoring Parameters
- Reassess at 48-72 hours: Children on appropriate therapy should demonstrate clinical improvement (reduced fever, improved respiratory effort, decreased oxygen requirement, improved feeding) within this timeframe 1, 2, 3
- If no improvement or deterioration occurs within 48-72 hours, further investigation is mandatory including chest radiography, blood cultures, and consideration of complications such as parapneumonic effusion or empyema 1
Common Pitfalls to Avoid
Underdosing amoxicillin is the most critical error—using standard doses (40-45 mg/kg/day) rather than high-dose (90 mg/kg/day) may lead to treatment failure with resistant pneumococci. 2 The difference for this child is substantial: standard dosing would be only 356-400 mg/day versus the recommended 800 mg/day.
Starting with a macrolide alone for presumed bacterial pneumonia should be avoided, as macrolides have high resistance rates among S. pneumoniae and should be reserved for atypical pathogens or added to beta-lactam therapy when the distinction is unclear. 2, 3
Failing to obtain appropriate follow-up within 48-72 hours is dangerous, as clinical deterioration or lack of improvement requires prompt reevaluation and potential change in management. 1, 2