Overlapping MERS and mild AESD caused by HHV-6 infection

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Mari Hatanaka1, Mitsuru Kashiwagi2, Takuya Tanabe3

  • 1Department of Pediatrics, Rakuwakai Otowa Hospital, Japan.

Brain & Development
|May 27, 2014
PubMed

Insights

This case study details a rare overlapping encephalopathy syndrome in a child, combining mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) and acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) due to human herpesvirus-6.

Area of Science:

  • Pediatric Neurology
  • Infectious Diseases
  • Neuroimaging

Background:

  • Human herpesvirus-6 (HHV-6) infections can cause various neurological complications in children.
  • Encephalopathy syndromes, such as MERS and AESD, are distinct neurological conditions.
  • Understanding overlapping presentations is crucial for accurate diagnosis and management.

Observation:

  • A 17-month-old girl presented with seizures following fever, initially showing a reversible splenial lesion on diffusion-weighted imaging (DWI).
  • The patient experienced a secondary seizure cluster with new fronto-subcortical white matter diffusion abnormalities on DWI.
  • Clinical and imaging findings indicated an overlapping MERS and mild AESD presentation.

Findings:

  • The case demonstrates a combined phenotype of MERS and mild AESD in a child infected with HHV-6.
  • Splenial lesions resolved, while fronto-subcortical lesions showed complete disappearance by Day 15.
  • The patient recovered without sequelae, highlighting the potential for full neurological recovery.

Implications:

  • This case suggests that combined encephalopathy syndromes can occur as a phenotype, challenging traditional classifications.
  • Recognizing overlapping syndromes is vital as they may not always present as independent entities.
  • Further research into combined encephalopathy presentations is warranted to refine diagnostic criteria and treatment strategies.
Keywords:
Acute encephalopathy with biphasic seizures and late reduced diffusionClinically mild encephalitis/encephalopathy with a reversible splenial lesionHuman herpesvirus 6Overlap

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