# Diagnosis of Acute Isolated Sphenoid Sinusitis Based on a Positive Kernig Sign in a Pediatric Patient

## TL;DR

A 14-year-old girl with a rare case of sphenoid sinusitis showed a Kernig sign, highlighting its potential as a diagnostic clue.

## Contribution

This is the first reported case linking a positive Kernig sign to acute isolated sphenoid sinusitis in a pediatric patient.

## Key findings

- Computed tomography showed fluid retention in the sphenoid sinus with normal cerebrospinal fluid findings.
- MRI revealed dural thickening and surgical findings indicated possible intracranial extension despite initial negative lumbar puncture.
- The Kernig sign resolved following treatment, suggesting its relevance to the condition.

## Abstract

Acute isolated sphenoid sinusitis in children is relatively rare, often presents with atypical symptoms, and may result in intracranial complications; therefore, early diagnosis is essential. We report the case of a 14-year-old girl who presented with a headache and a positive Kernig sign. Computed tomography (CT) demonstrated fluid retention in the sphenoid sinus, and lumbar puncture showed no abnormalities in the cerebrospinal fluid (CSF). Based on these findings, she was diagnosed with acute isolated sphenoid sinusitis without intracranial complications. However, the patient showed a poor response to antibiotic therapy, and magnetic resonance imaging (MRI) revealed dural thickening, necessitating surgical intervention. Intraoperatively, bony destruction and CSF leakage were identified, suggesting extension of inflammation into intracranial structures. Following treatment, the patient’s Kernig sign resolved. To our knowledge, there have been no previous reports explicitly describing the appearance of the Kernig sign in sphenoid sinusitis. This case provides important insights into the clinical significance of this finding.