What is the first-line treatment for a child with rhinosinusitis?

First-Line Treatment for Pediatric Rhinosinusitis

For children with acute bacterial rhinosinusitis, amoxicillin at 45 mg/kg/day (or 80-90 mg/kg/day in high-risk situations) is the first-line antibiotic treatment, but watchful waiting with symptomatic management is appropriate for most children with post-viral rhinosinusitis. 1

Distinguishing Viral from Bacterial Disease

The critical first step is determining whether the child has viral/post-viral rhinosinusitis (most common) or acute bacterial rhinosinusitis (ABRS), as this fundamentally changes management:

• Viral/post-viral rhinosinusitis is self-limiting and does not require antibiotics 2
• ABRS should be suspected when symptoms persist beyond 10 days without improvement, when symptoms worsen after initial improvement (double-worsening), or when severe symptoms (fever ≥39°C, purulent nasal discharge) are present for at least 3-4 consecutive days 1

First-Line Treatment for Post-Viral Rhinosinusitis

For the majority of children with post-viral rhinosinusitis, antibiotics are NOT recommended as they show no benefit for cure or significant improvement 2. Instead:

• Herbal medicines (BNO1016 tablets, Pelargonium sidoides drops, Myrtol capsules) are recommended as first-line treatment, showing significant symptom improvement without adverse events 2
• Bacterial lysates (OM-85-BV) can shorten illness duration 2
• High-volume nasal saline irrigation is beneficial for purulent rhinorrhea and post-nasal drip 2
• Nasal saline spray provides symptomatic relief 2

What NOT to Use in Children

• Antibiotics: Not indicated for post-viral disease 2
• Nasal corticosteroids: Very low quality evidence, not recommended 2
• Antihistamines: No additive benefit 2
• OTC cough and cold medications: Contraindicated under age 2 years due to lack of efficacy and potential toxicity; should be avoided under age 6 years 1, 2
• Topical decongestants: Not recommended under age 1 year due to narrow therapeutic window and cardiovascular/CNS risks; risk of rhinitis medicamentosa after 3-4 days of use 1, 2

First-Line Antibiotic Treatment for Acute Bacterial Rhinosinusitis

When ABRS is diagnosed and antibiotic treatment is warranted:

Standard-Dose Amoxicillin (First-Line)

For children ≥2 years with mild-to-moderate disease, no recent antibiotic use, and not in daycare:

• Amoxicillin 45 mg/kg/day divided twice daily for 5-10 days 1
• Maximum 2 grams per dose 1

High-Dose Amoxicillin-Clavulanate (First-Line for High-Risk)

For children with ANY of the following risk factors:

• Age <2 years 1
• Daycare attendance 1
• Antibiotic use within past 30 days 1
• Moderate-to-severe illness 1
• Geographic areas with >10% penicillin-nonsusceptible S. pneumoniae 1

Dosing: Amoxicillin-clavulanate 80-90 mg/kg/day (of amoxicillin component) with 6.4 mg/kg/day clavulanate, divided twice daily 1

• Maximum 2 grams per dose 1
• This dosing overcomes resistance from altered penicillin-binding proteins in S. pneumoniae and inhibits β-lactamase-producing H. influenzae and M. catarrhalis 1

Alternative for Non-Adherent or Vomiting Patients

Single-dose ceftriaxone 50 mg/kg IV or IM can be used for children who cannot tolerate oral medication or when adherence is uncertain 1

• Effective against 95-100% of the three major pathogens (S. pneumoniae, H. influenzae, M. catarrhalis) 1

Penicillin-Allergic Patients

For children with true penicillin allergy:

• Second- or third-generation cephalosporins (e.g., cefdinir, cefpodoxime, cefuroxime) are appropriate alternatives 3
• Clarithromycin may be used in β-lactam allergic patients 3
• Clindamycin for culture-proven penicillin-resistant S. pneumoniae 3

Duration of Treatment

• 5-10 days is the recommended duration for most cases of ABRS 1
• The evidence for optimal duration is limited, but this range balances efficacy with minimizing resistance 1

When to Reassess

Reevaluate within 72 hours if:

• No improvement occurs 2
• Symptoms worsen at any time 1, 2

Immediate referral required for alarm symptoms:

• Displaced globe (orbital complications) 2
• Respiratory distress (rate >70 breaths/min in infants, >50 in older children) 2
• Persistent high fever despite treatment 2

Key Microbiology Considerations

The three major pathogens in pediatric ABRS are:

• Streptococcus pneumoniae (~30%) 1
• Haemophilus influenzae (~30%) 1
• Moraxella catarrhalis (~10%) 1

Approximately 10-15% of S. pneumoniae are penicillin-nonsusceptible nationally, though this varies by region (up to 50-60% in some areas) 1. Between 10-42% of H. influenzae and nearly 100% of M. catarrhalis produce β-lactamase 1. This resistance pattern justifies the use of high-dose amoxicillin or amoxicillin-clavulanate in high-risk populations.

Common Pitfalls to Avoid

• Over-prescribing antibiotics for viral disease: Most pediatric rhinosinusitis is viral and self-resolves within 7-10 days 2, 4
• Using broad-spectrum antibiotics as first-line: This increases resistance without improving outcomes 1
• Prescribing OTC cold medications to young children: These lack efficacy and carry toxicity risks 1, 2
• Failing to identify high-risk patients: Children <2 years, in daycare, or with recent antibiotic exposure require more aggressive initial therapy 1
• Not counseling about watchful waiting: For ABRS, watchful waiting for up to 7 days with symptomatic relief is appropriate when follow-up is ensured 1