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Two newly proposed infectious encephalitis/encephalopathy syndromes
1Department of Pediatrics, Kameda Medical Center, 929 Higashi-cho, Kamogawa-shi, Chiba 296-8602, Japan. jtaka@kameda.jp
Brain & Development
|April 3, 2009
Summary
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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