What is the best initial treatment for a pediatric patient with a runny nose, upper respiratory tract infection (URTI) symptoms, and subsequent development of frontal tenderness 3 days later?

Start Amoxicillin Immediately

For a pediatric patient with URTI symptoms followed by frontal tenderness at 3 days, you should start amoxicillin immediately without obtaining a CT scan. This presentation meets criteria for acute bacterial sinusitis with a "worsening course," which mandates antibiotic therapy rather than observation or imaging. 1

Why Antibiotics Are Indicated

This clinical scenario represents a "worsening course" presentation of acute bacterial sinusitis—defined as worsening or new onset of symptoms (frontal tenderness) after initial URTI symptoms. 1 The American Academy of Pediatrics explicitly states that clinicians should prescribe antibiotic therapy for children with a worsening course presentation. 1

Frontal sinusitis specifically requires definitive antibiotic treatment. Unlike maxillary sinusitis where observation may be considered in some cases, frontal sinusitis carries higher risk of complications and warrants immediate antibiotics. 1 The French guidelines emphasize that "antibiotic therapy is definitely indicated in the case of frontal, ethmoidal or sphenoidal sinusitis." 1

Why CT Scan Is Not Indicated

Imaging studies should NOT be obtained to distinguish acute bacterial sinusitis from viral URI, as they do not contribute to the diagnosis in uncomplicated cases. 1, 2 The American Academy of Pediatrics is explicit that clinicians should not obtain imaging studies of any kind for diagnosis of uncomplicated acute bacterial sinusitis. 1

CT scanning is reserved exclusively for suspected complications such as: 1

• Periorbital or orbital swelling with proptosis
• Impaired extraocular muscle function or visual changes
• Severe headache with altered mental status
• Signs of intracranial involvement

Recommended Antibiotic Regimen

First-line treatment is amoxicillin or amoxicillin-clavulanate. 1, 3, 2

Standard dosing options:

• Standard-dose amoxicillin: 45 mg/kg/day divided every 8-12 hours 1
• High-dose amoxicillin-clavulanate: 90 mg/kg/day (of amoxicillin component) divided every 12 hours 1, 3

When to use high-dose amoxicillin-clavulanate: 1, 3

• Child younger than 2 years
• Daycare attendance
• Recent antibiotic exposure (within 4-6 weeks)
• Geographic areas with high prevalence of resistant Streptococcus pneumoniae
• Severe symptoms at presentation

For frontal sinusitis specifically, amoxicillin-clavulanate provides broader coverage and is preferred over amoxicillin alone. 1, 2 The French guidelines list amoxicillin-clavulanate as first-line for frontal sinusitis. 1

Treatment Duration

Treat for 10-14 days total. 1, 3 The American Academy of Pediatrics recommends 10-14 days for acute bacterial sinusitis, with duration individualized based on clinical response but with a minimum of 10 days. 3

Mandatory Reassessment

You must reassess within 72 hours. 1, 3, 2 If the child shows worsening symptoms or failure to improve within 72 hours of starting antibiotics, you should either change to a broader-spectrum antibiotic (such as high-dose amoxicillin-clavulanate if not already prescribed, or clindamycin plus cefixime) or consider complications requiring imaging. 1

Why Reassurance Alone Is Inadequate

Simple reassurance without treatment is inappropriate for this presentation. 1 While observation for 3 days may be considered for persistent illness (symptoms >10 days without worsening), this child has a worsening course with new frontal tenderness developing after initial URTI symptoms. 1 The worsening course presentation requires immediate antibiotic therapy, not watchful waiting. 1

Critical Red Flags Requiring Immediate Imaging and Hospitalization

Watch for complications that would necessitate contrast-enhanced CT and hospital admission: 1, 3, 2

• Periorbital edema or erythema (>50% eyelid closure)
• Proptosis or impaired extraocular movements
• Visual changes or painful eye movements
• Severe headache with altered mental status
• Meningeal signs
• Facial swelling suggesting abscess

If any of these develop, obtain contrast-enhanced CT immediately and consult otolaryngology, ophthalmology, and infectious disease. 1