Unilateral meningoencephalitis with hemispheric slowing on EEG

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H Takeuchi1, T Iguchi, T Ishikawa

  • 1Department of Pediatrics, Nagoya City University Medical School, Japan.

Brain & Development
|January 1, 1997
PubMed

Insights

A boy with non-herpes simplex virus meningoencephalitis had subtle right brain dysfunction. Electroencephalograms (EEGs) revealed prolonged slowing, guiding diagnosis despite normal neuroimaging.

Area of Science:

  • Neurology
  • Pediatric Neurology
  • Neuroinfectious Diseases

Background:

  • Meningoencephalitis, an inflammation of the brain and meninges, can present with diverse neurological symptoms.
  • Non-herpes simplex virus (HSV) etiologies are less common but crucial to identify for appropriate management.
  • Pediatric cases often require careful diagnostic evaluation due to potential for subtle presentations.

Observation:

  • A 12-year-old male presented with seizures affecting left extremities and loss of consciousness.
  • Initial neuroimaging studies, including MRI or CT, revealed normal findings.
  • Interictal electroencephalograms (EEGs) demonstrated prolonged slowing predominantly in the right cerebral hemisphere.

Findings:

  • The unilateral EEG abnormalities correlated with right-sided brain dysfunction identified through neuropsychological testing.
  • This case highlights a non-HSV meningoencephalitis with focal neurological deficits.
  • The findings underscore the utility of EEG in detecting subtle brain dysfunction when neuroimaging is unremarkable.

Implications:

  • Electroencephalography (EEG) plays a critical role in diagnosing subtle encephalitis, especially when neuroimaging is normal.
  • Early identification of lateralized brain dysfunction is essential for targeted treatment and prognosis.
  • This case emphasizes the importance of considering non-HSV causes of meningoencephalitis in pediatric patients.

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