In an 11-year-old girl with sudden severe headache, repeated vomiting, malaise, drowsiness, no fever or trauma, normal neurological exam, and a non-contrast head CT showing only left frontal sinusitis with normal white blood cell count and C-reactive protein, what is the appropriate next step in evaluation and management?

Immediate Contrast-Enhanced CT or MRI of Brain and Sinuses is Required

This 11-year-old requires urgent contrast-enhanced CT or MRI to evaluate for intracranial complications of sinusitis, given the constellation of severe headache, repeated vomiting, drowsiness, and frontal sinusitis—even with normal inflammatory markers and no fever. 1, 2

Critical Clinical Context

This presentation is highly concerning for intracranial extension of sinusitis despite the reassuring laboratory values. The guidelines are explicit: intracranial complications should be suspected in any child with sinusitis who presents with severe headache, photophobia, seizures, altered consciousness, or other focal neurologic findings 1. Your patient has three of these red flags:

• Severe sudden headache (sudden onset, requiring ED visit)
• Altered consciousness (drowsiness/malaise)
• Repeated vomiting (5 episodes—suggests increased intracranial pressure)

The inability to clearly perform the Barré maneuver adds subtle concern for possible weakness, though this may be effort-dependent.

Why Normal Labs Don't Rule Out Serious Complications

The normal WBC (10,800) and CRP (<0.6 mg/L) are falsely reassuring. Intracranial complications of sinusitis can occur with minimal systemic inflammatory response, particularly in early stages or when infection is localized to closed spaces (epidural/subdural empyema, brain abscess) 2. Multiple case reports document intracranial complications presenting with normal or minimally elevated inflammatory markers 3, 4, 5, 6.

Specific Imaging Recommendation

Order contrast-enhanced CT of the brain and paranasal sinuses immediately 1, 7. If CT is equivocal or shows concerning findings, proceed directly to MRI with contrast 2, 7.

The ACR Appropriateness Criteria and AAP guidelines are unambiguous: contrast-enhanced imaging (CT or MRI) should be performed in children thought to have orbital or central nervous system complications of sinusitis 1, 2. The frontal sinusitis on non-contrast CT is the source, and the clinical presentation suggests intracranial extension.

Why Contrast is Essential

Non-contrast CT already shows the sinusitis but cannot adequately evaluate for:

• Epidural or subdural empyema (most common intracranial complication from frontal sinusitis) 2
• Brain abscess
• Meningitis/cerebritis
• Venous sinus thrombosis
• Orbital complications

Frontal sinusitis is the most common source of intracranial complications via retrograde spread through valveless diploic veins 2. This patient's frontal sinusitis with severe neurological symptoms fits this pattern exactly.

Immediate Management Algorithm

While arranging imaging:

1. Admit to hospital immediately with neurosurgical and ENT consultation on standby
2. Start broad-spectrum IV antibiotics immediately—do not wait for imaging 1, 7
   • Vancomycin (for MRSA and resistant Streptococcus pneumoniae) PLUS
   • Third-generation cephalosporin (ceftriaxone or cefotaxime) PLUS
   • Metronidazole (for anaerobic coverage)
3. Obtain contrast-enhanced imaging emergently (within 1-2 hours)
4. Serial neurological examinations every 1-2 hours—deterioration can be rapid 4, 6

Common Pitfalls to Avoid

Do NOT:

• Dismiss symptoms because of normal inflammatory markers—CRP and WBC are unreliable for intracranial complications 3, 4, 5, 6
• Attribute symptoms to "viral sinusitis" and discharge home
• Delay imaging to "observe" the patient—intracranial complications can progress within hours 4, 6
• Order non-contrast imaging only—you need contrast to see empyema, abscess, and meningeal enhancement 2, 7

Critical timing issue: The guidelines note that intracranial complications present with nonspecific symptoms initially (headache, vomiting, malaise) but can evolve rapidly to permanent brain damage or death 3, 4, 6. The drowsiness in your patient suggests this process may already be underway.

Expected Findings and Next Steps

If imaging shows intracranial complication:

• Immediate combined neurosurgical and ENT surgical intervention (craniotomy for empyema drainage + endoscopic sinus surgery) 3, 4
• Continue IV antibiotics for 4-6 weeks 3, 4
• ICU-level monitoring

If imaging is negative:

• Continue IV antibiotics for acute bacterial sinusitis
• Close neurological monitoring for 48-72 hours
• Consider lumbar puncture if meningitis remains a concern (though less likely with normal CT)
• Repeat imaging if symptoms worsen or fail to improve

Why This Differs from Uncomplicated Sinusitis

The AAP guidelines clearly state that imaging is NOT recommended for uncomplicated acute bacterial sinusitis 1, 2. However, your patient has complicated sinusitis by definition—the severe headache, drowsiness, and repeated vomiting are neurological symptoms that mandate investigation for intracranial extension 1, 2.

The mortality and morbidity of missed intracranial complications are substantial, while the risk of contrast-enhanced imaging is minimal 2. When intracranial complications are suspected, the benefit-risk ratio overwhelmingly favors aggressive imaging and treatment 1, 7.