What is the appropriate management for an afebrile 18‑month‑old with three weeks of persistent rhinorrhea and nasal congestion?

Management of 3 Weeks Nasal Discharge with Congestion in an Afebrile 18-Month-Old

This 18-month-old with 3 weeks of nasal discharge and congestion without fever meets 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 Reasoning

This clinical presentation fulfills the American Academy of Pediatrics definition of persistent acute bacterial sinusitis:

• Nasal discharge (of any quality) lasting ≥10 days without improvement 1, 2
• Duration of 3 weeks (21 days) clearly exceeds the 10-day threshold 1, 2
• Absence of fever does not exclude bacterial sinusitis; the "persistent" pattern requires only nasal discharge or cough for ≥10 days without improvement 1

Key distinction from viral upper respiratory infection: Most viral URIs resolve by 10 days, with mucus that starts clear, becomes cloudy, then improves 1. This child's symptoms have persisted for 21 days without improvement, making bacterial superinfection the most likely diagnosis 1, 2.

Why Antibiotics Are Indicated (Not Observation)

Although the 2013 AAP guideline permits either immediate antibiotics or 3 additional days of observation for persistent illness, antibiotic therapy is strongly favored at 21 days of symptoms:

• The number needed to treat with antibiotics is only 3–5 to achieve clinical cure at 10–14 days 1, 2
• Three weeks of symptoms represents substantial impairment of quality of life 1
• The European position paper shows no benefit of antibiotics for post-viral rhinosinusitis in the first 10 days 1, but this child is well beyond that window
• Supportive care alone is inappropriate once bacterial infection is established at >10 days 2

First-Line Antibiotic Regimen

Prescribe oral amoxicillin 45 mg/kg/day divided into two daily doses for 10–14 days (or until symptom-free for 7 days). 2

Standard-dose amoxicillin is appropriate for this child unless specific risk factors are present:

• High-dose amoxicillin (80–90 mg/kg/day) or amoxicillin-clavulanate should be reserved for children with: age <2 years, daycare attendance, antibiotic use in past 4–6 weeks, or residence in areas with high penicillin-resistant S. pneumoniae prevalence 1, 2, 3
• At 18 months, this child is close to the 2-year threshold; if any of the other risk factors are present, escalate to high-dose amoxicillin-clavulanate (90 mg/kg/day of amoxicillin component) 2, 3

The most common bacterial pathogens are Streptococcus pneumoniae (30%), non-typeable Haemophilus influenzae (30%), and Moraxella catarrhalis (~10%). 2

Imaging Is Not Indicated

Do not obtain sinus X-rays or CT scans for this uncomplicated case:

• The American College of Radiology states that sinus imaging does not change management in uncomplicated acute bacterial sinusitis 2
• More than 50% of children with viral URIs and 42% of healthy children show abnormal sinus radiographs, making imaging non-specific 2
• Imaging is reserved exclusively for suspected orbital complications (periorbital swelling, proptosis, ophthalmoplegia) or intracranial complications (altered mental status, severe headache, focal neurologic deficits) 1, 2

Mandatory 72-Hour Reassessment

Schedule follow-up at 72 hours after starting amoxicillin to assess for:

• Worsening symptoms: New fever, increased purulent discharge, or severe headache indicate treatment failure and require escalation to high-dose amoxicillin-clavulanate 1, 2
• Lack of improvement: If no clinical improvement by 72 hours, escalate to high-dose amoxicillin-clavulanate 1, 2
• Orbital complications: Periorbital swelling, proptosis, or impaired extraocular movements require immediate imaging and specialist consultation 1, 2
• Intracranial complications: Altered mental status, severe headache, or focal neurologic signs necessitate emergent CT and neurosurgical evaluation 1, 2

Common Pitfalls to Avoid

Do not delay antibiotic therapy beyond the current 21-day mark: Although brief observation is permitted for symptoms at exactly 10 days, this child has already had 3 weeks of illness and requires treatment 1, 2

Do not prescribe antihistamines for primary treatment: The AAP expert panel states antihistamines should not be used for acute bacterial sinusitis, though they may help allergic symptoms in atopic children 1

Do not start with amoxicillin-clavulanate unless risk factors for resistance are documented: Standard amoxicillin remains first-line for uncomplicated disease 2

Do not attribute prolonged nasal symptoms to "just a cold": Viral URIs improve by 10 days; persistence beyond this threshold indicates bacterial superinfection requiring antibiotics 1, 2

Do not overlook underlying conditions if this becomes recurrent: If this child develops ≥4 episodes per year, evaluate for allergic rhinitis, immunodeficiency, cystic fibrosis, gastroesophageal reflux, or ciliary dysfunction 1, 3