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Two newly proposed infectious encephalitis/encephalopathy syndromes

Jun-ichi Takanashi1

  • 1Department of Pediatrics, Kameda Medical Center, 929 Higashi-cho, Kamogawa-shi, Chiba 296-8602, Japan. jtaka@kameda.jp

Brain & Development
|April 3, 2009
PubMed

Insights

Two infant encephalopathy syndromes, Acute Encephalopathy with Biphasic Seizures and Late Reduced Diffusion (AESD) and Clinically Mild Encephalitis/Encephalopathy with a Reversible Splenial Lesion (MERS), are reviewed. MRI is crucial for diagnosing these conditions, which present distinct clinical and imaging features.

Area of Science:

  • Neurology
  • Pediatrics
  • Radiology

Background:

  • Two novel syndromes of infectious encephalitis/encephalopathy require magnetic resonance imaging (MRI) for diagnosis.
  • Acute Encephalopathy with Biphasic Seizures and Late Reduced Diffusion (AESD) and Clinically Mild Encephalitis/Encephalopathy with a Reversible Splenial Lesion (MERS) are distinct neurological conditions.

Purpose of the Study:

  • To review the diagnostic criteria and clinical characteristics of AESD and MERS.
  • To highlight the essential role of MRI in differentiating these encephalopathy syndromes.

Main Methods:

  • Review of existing literature on AESD and MERS.
  • Analysis of clinical presentations and MRI findings associated with each syndrome.

Main Results:

  • AESD, exclusive to East Asian infants, presents with biphasic seizures and characteristic white matter diffusion changes on MRI.
  • MERS involves a reversible splenial lesion in the corpus callosum, often with transient diffusion restriction, and typically resolves within a month.

Conclusions:

  • MRI is indispensable for the diagnosis and characterization of AESD and MERS.
  • Understanding the unique imaging patterns and clinical courses of these syndromes aids in accurate diagnosis and management.

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