What is the appropriate treatment for a 2‑year‑old child with acute bacterial sinusitis?

Treatment of Bacterial Sinusitis in a 2-Year-Old

Start high-dose amoxicillin-clavulanate (90 mg/kg/day of the amoxicillin component + 6.4 mg/kg/day clavulanate, divided twice daily) immediately for 10–14 days, because children under 2 years have high rates of penicillin-resistant Streptococcus pneumoniae and β-lactamase-producing organisms. 1

Why High-Dose Amoxicillin-Clavulanate Is Mandatory at This Age

• Age < 2 years is an explicit risk factor that requires high-dose amoxicillin-clavulanate rather than standard amoxicillin from the outset, according to the American Academy of Pediatrics (AAP). 1

• Toddlers have higher nasopharyngeal colonization with β-lactamase-producing Haemophilus influenzae and Moraxella catarrhalis, plus higher rates of penicillin-resistant S. pneumoniae. 1

• Standard-dose amoxicillin (45 mg/kg/day) is not appropriate for children younger than 2 years; do not use it as first-line therapy in this age group. 1

• Other risk factors that also mandate high-dose therapy include daycare attendance, antibiotic use within the prior 4–6 weeks, or residence in regions where >10% of S. pneumoniae isolates are penicillin-resistant. 1, 2

Dosing and Formulation

• For a typical 2-year-old weighing 12–14 kg, the calculated amoxicillin dose is approximately 1,080–1,260 mg/day (540–630 mg twice daily). 1

• Use the 14:1 amoxicillin-to-clavulanate formulation to minimize diarrhea while preserving adequate β-lactamase inhibition. 1

• Treat for a minimum of 10–14 days, or continue antibiotics for 7 days after the child becomes symptom-free, whichever period is longer. 1, 2

Mandatory 72-Hour Reassessment

• The AAP requires reassessment exactly 72 hours after initiating antibiotics to identify treatment failure or emerging complications. 1, 2

• Indicators of failure at 72 hours include:

  • New or worsening fever 1, 2
  • Increased purulent nasal discharge 1, 2
  • Severe headache 1, 2

• If failure is confirmed while the child is already on high-dose amoxicillin-clavulanate:

  • Administer a single dose of intramuscular ceftriaxone (50 mg/kg) if oral intake is not possible 1
  • Promptly evaluate for orbital or intracranial complications 1
  • Consider pediatric infectious-disease or ENT consultation 1

Recognition of Complications (Requires Immediate Action)

• Orbital complications are suspected with periorbital swelling, proptosis, restricted eye movements, or visual changes. 1, 2

• Intracranial complications are suspected with altered mental status, severe headache, seizures, or focal neurologic deficits. 1, 2

• Management of any complication includes:

  • Urgent contrast-enhanced CT imaging 1, 2
  • Intravenous antibiotics covering typical pathogens (e.g., vancomycin + ceftriaxone or cefotaxime) 1
  • Immediate ENT and/or neurosurgery consultation 1

Alternative Regimens for Vomiting or Non-Compliance

• When oral therapy is not tolerated, administer a single dose of ceftriaxone 50 mg/kg IM or IV (approximately 600–700 mg for a 12–14 kg child). 1

• Thereafter, switch back to oral high-dose amoxicillin-clavulanate to complete the full course. 1

Penicillin-Allergy Alternatives

• For children with non-severe (non-IgE-mediated) penicillin allergy, a second- or third-generation oral cephalosporin (e.g., cefdinir, cefuroxime axetil, or cefpodoxime) for 10 days is recommended; cross-reactivity with penicillins is negligible. 1

• Azithromycin or trimethoprim-sulfamethoxazole should not be used as first-line agents because resistance rates in S. pneumoniae and H. influenzae exceed 20–25%. 1

• Do not prescribe first-generation cephalosporins (e.g., cephalexin) because they lack adequate coverage against β-lactamase-producing H. influenzae. 1

Diagnostic Criteria (Clinical Diagnosis Only—No Imaging)

• The AAP advises that acute bacterial sinusitis in this age group should be diagnosed on clinical grounds alone; routine sinus imaging (X-ray or CT) is not indicated for uncomplicated cases. 1, 2

• Clinical patterns that define acute bacterial sinusitis are:

  • Persistent illness – nasal discharge (any quality) or daytime cough lasting ≥10 days without improvement 1
  • Severe onset – fever ≥39°C for ≥3 consecutive days together with thick, purulent nasal discharge 1
  • Worsening course – new fever ≥38°C or a marked increase in cough/discharge after an initial improvement from a viral upper-respiratory infection 1, 2

• CT scanning is reserved exclusively for suspected complications, such as periorbital or orbital swelling with proptosis, impaired extraocular muscle function or visual changes, severe headache with altered mental status, or signs of intracranial involvement. 2

Epidemiology of Common Pathogens

• Streptococcus pneumoniae accounts for roughly 30% of pediatric acute bacterial sinusitis cases. 1

• Nontypeable Haemophilus influenzae accounts for about 20–30% of cases. 1

• Moraxella catarrhalis accounts for approximately 10–20% of cases. 1

Common Pitfalls to Avoid

• Do not start with standard-dose amoxicillin (45 mg/kg/day) in children < 2 years; high-dose amoxicillin-clavulanate is required from the outset. 1

• Do not obtain sinus imaging for uncomplicated disease; reserve imaging for suspected orbital or intracranial complications. 1, 2

• Do not use antihistamines as primary therapy for acute bacterial sinusitis. 1

• Do not delay the 72-hour reassessment; early detection of failure prevents progression to complications. 1