In a child with a two‑week history of green nasal discharge, how should I evaluate and manage possible acute bacterial sinusitis?

Management of a Child with Two Weeks of Green Nasal Discharge

This child meets diagnostic criteria for persistent acute bacterial sinusitis and should be started on oral amoxicillin 45 mg/kg/day divided twice daily for 10–14 days. 1, 2

Diagnostic Confirmation

The American Academy of Pediatrics defines persistent acute bacterial sinusitis as nasal discharge (of any quality) or daytime cough lasting more than 10 days without improvement. 1 This child's two-week history clearly exceeds the 10-day threshold required for diagnosis. 2

Key diagnostic points:

• The diagnosis is entirely clinical—no imaging is required for uncomplicated cases. 1, 2
• Green or purulent nasal discharge is common in both viral and bacterial infections; the duration beyond 10 days is what distinguishes bacterial sinusitis from a prolonged viral URI. 1, 2
• Fever is not required for the diagnosis of persistent acute bacterial sinusitis. 1, 2
• Most viral upper respiratory infections resolve by day 10, so persistence beyond this point suggests bacterial superinfection. 2

First-Line Antibiotic Therapy

Standard-dose amoxicillin (45 mg/kg/day divided twice daily) is the first-line treatment for uncomplicated persistent acute bacterial sinusitis in children. 1, 2

Treatment duration:

• Continue for 10–14 days total, or until the child is symptom-free for at least 7 days. 1, 2

The number needed to treat (NNT) with antibiotics is 3–5 to achieve clinical cure, indicating substantial benefit over observation alone. 2

When to Escalate to High-Dose Therapy

High-dose amoxicillin (80–90 mg/kg/day) or amoxicillin-clavulanate should be used if the child has any of these risk factors: 1, 2

• Age < 2 years
• Daycare attendance
• Recent antibiotic use (within past 4–6 weeks)
• Residence in an area with high prevalence of penicillin-resistant Streptococcus pneumoniae

If none of these risk factors are present, start with standard-dose amoxicillin. 2

Mandatory 72-Hour Reassessment

The child must be reassessed exactly 72 hours after starting amoxicillin to detect treatment failure or complications. 1, 2, 3

At the 72-hour follow-up, evaluate for:

• Worsening symptoms (new fever ≥38°C, increased purulent discharge, severe headache) → escalate immediately to high-dose amoxicillin-clavulanate (90 mg/kg/day of the amoxicillin component). 1, 2, 3
• Lack of improvement → consider escalation to high-dose amoxicillin-clavulanate. 1, 2, 3
• Orbital complications (periorbital swelling, proptosis, impaired eye movements) → obtain urgent contrast-enhanced CT and specialist consultation. 1, 2, 3
• Intracranial complications (altered mental status, severe headache, photophobia, seizures, focal neurologic deficits) → emergent CT and neurosurgical evaluation. 1, 2, 3

Imaging Recommendations

Do not obtain sinus X-rays or CT scans for uncomplicated cases. 1, 2

• More than 50% of children with viral URIs show abnormal sinus radiographs, and 42% of healthy children have sinus abnormalities on imaging, making radiographs non-specific. 2
• Imaging is reserved exclusively for suspected orbital or intracranial complications. 1, 2

Common Pitfalls to Avoid

• Do not delay antibiotic therapy once symptoms exceed 10 days; although the AAP permits a brief 3-day observation period at exactly 10 days for persistent cases without severe features, this child is already at 14 days and should be treated immediately. 1, 2
• Do not start with amoxicillin-clavulanate unless risk factors for resistant organisms are present; standard amoxicillin remains first-line for uncomplicated disease. 1, 2
• Do not attribute prolonged nasal symptoms to a simple "cold" when they persist beyond 10 days, as this indicates likely bacterial superinfection. 2
• Do not use supportive care alone once symptoms have persisted >10 days; antibiotics provide higher cure rates than observation. 2

Microbiology

The major bacterial pathogens in pediatric acute bacterial sinusitis are: 1, 2

• Streptococcus pneumoniae (~30%)
• Nontypeable Haemophilus influenzae (~30%)
• Moraxella catarrhalis (~10%)