In a 5‑year‑old girl weighing 27 kg with a 2‑day history of fever and productive cough producing green sputum, what is the most likely diagnosis and what are the appropriate doses of co‑amoxiclav (amoxicillin/clavulanic acid) and paracetamol?

Diagnosis and Treatment of Bacterial Lower Respiratory Tract Infection in a 5-Year-Old Child

This 5-year-old child with fever and productive cough with greenish sputum most likely has bacterial community-acquired pneumonia, and should be treated with high-dose amoxicillin 80-100 mg/kg/day divided into three doses, which equals approximately 720-900 mg three times daily (total 2,160-2,700 mg/day) for this 27 kg child. 1, 2

Most Likely Diagnosis

Bacterial community-acquired pneumonia is the primary diagnosis based on:

• Fever with productive cough yielding greenish sputum strongly indicates bacterial rather than viral etiology in this age group 2
• Streptococcus pneumoniae is the most common bacterial pathogen in children under 5 years with pneumonia 1, 3
• The 2-day duration with purulent sputum production supports bacterial infection 1, 2

Antibiotic Treatment: Co-Amoxiclav vs. Amoxicillin

First-Line Recommendation: High-Dose Amoxicillin

Amoxicillin alone is the preferred first-line treatment, NOT co-amoxiclav, unless specific risk factors are present. 1, 2

Dosing for this 27 kg child:

• Amoxicillin: 80-100 mg/kg/day = 2,160-2,700 mg/day divided into THREE doses 1, 2
• This equals 720-900 mg three times daily 1, 2
• Duration: 10 days 1, 2

When Co-Amoxiclav IS Indicated

Co-amoxiclav (amoxicillin-clavulanate) should be used instead of amoxicillin alone ONLY if any of these risk factors are present: 1, 2

• Incomplete immunization against Haemophilus influenzae type b or Streptococcus pneumoniae 2
• Coexistent purulent acute otitis media 2
• Recent antibiotic exposure (within past 3 months) 2
• Treatment failure after 48-72 hours on amoxicillin 2

If co-amoxiclav is indicated, the correct dosing for this 27 kg child is:

• 80-100 mg/kg/day of the amoxicillin component = 2,160-2,700 mg/day divided into THREE doses 1, 2
• This equals approximately 15-18 mL of the 457 mg/5 mL suspension three times daily (NOT twice daily as suggested in your question) 1, 2

Critical Dosing Error in Your Proposed Regimen

The proposed "co-amoxiclav 457 mg/5 mL BID for 7 days" is INCORRECT for two reasons: 1, 2

1. Frequency error: Pediatric pneumonia requires THREE times daily dosing, not twice daily, to maintain adequate drug levels against S. pneumoniae 1, 2
2. Duration may be inadequate: While 7 days may be acceptable in some guidelines, 10 days is recommended for pneumococcal pneumonia to ensure complete eradication 2

Paracetamol (Acetaminophen) Dosing

For this 27 kg child:

• Dose: 15 mg/kg per dose = 405 mg per dose (can round to 400 mg) 1
• Frequency: Every 4-6 hours as needed 1
• Maximum daily dose: 75 mg/kg/day = 2,025 mg/day (do not exceed) 1
• Purpose: Fever control and comfort; helps reduce metabolic demands and oxygen requirements 1

Clinical Monitoring and Reassessment

Reassess at 48-72 hours of treatment: 1, 2

• Fever should resolve within 24-48 hours if the antibiotic is effective 2
• Overall clinical improvement (reduced respiratory distress, better feeding) should be evident by 48-72 hours 2
• Cough may persist longer and should not be used as the sole indicator of treatment failure 2

Signs Requiring Immediate Re-evaluation

Return immediately or call if any of these develop: 1, 2

• Worsening respiratory distress or increased work of breathing 2
• Oxygen saturation ≤92% on room air 1, 2
• Persistent fever beyond 48-72 hours of treatment 2
• Inability to maintain oral intake or signs of dehydration 1, 2
• Altered mental status or lethargy 2

Management of Treatment Failure (No Improvement at 48-72 Hours)

If no improvement after 48-72 hours on appropriate amoxicillin therapy: 2

• Consider atypical pathogens (Mycoplasma pneumoniae, Chlamydophila pneumoniae) 1, 2
• Switch to or add azithromycin: 10 mg/kg on day 1, then 5 mg/kg daily on days 2-5 2
• Obtain chest radiography to rule out complications such as empyema 2

Important Clinical Pitfalls to Avoid

• Do NOT use chest physiotherapy – it provides no benefit in pediatric pneumonia and should be omitted 1, 2
• Do NOT prescribe antibiotics for mild lower respiratory symptoms without clear evidence of bacterial infection, as most cases in young children are viral 1, 2, 4
• Do NOT assume all cephalosporins are equivalent – first-generation agents like cephalexin have inadequate activity against respiratory pathogens 5
• Do NOT use twice-daily dosing for standard amoxicillin or co-amoxiclav in pediatric pneumonia – three times daily is required 1, 2

Summary of Correct Prescribing for This Case

If no risk factors present (preferred):

• Amoxicillin 720-900 mg three times daily for 10 days 1, 2

If risk factors present:

• Co-amoxiclav 15-18 mL (of 457 mg/5 mL suspension) three times daily for 10 days 1, 2

Plus:

• Paracetamol 400 mg every 4-6 hours as needed for fever (max 2,025 mg/day) 1
• Ensure adequate hydration 1
• Reassess at 48-72 hours 1, 2