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Fibrous dysplasia in a child with mitochondrial A8344G mutation

Szu-Ta Chen1, Pi-Chuan Fan, Wuh-Liang Hwu

  • 1Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan.

Journal of Child Neurology
|September 6, 2008
PubMed

Insights

A rare case links Myoclonic Epilepsy with Ragged Red Fibers (MERRF) syndrome, caused by mitochondrial A8344G DNA mutation, to fibrous dysplasia. This highlights the need for skeletal evaluation in MERRF patients presenting with focal symptoms.

Area of Science:

  • Mitochondrial genetics
  • Neurology
  • Developmental disorders

Background:

  • Myoclonic Epilepsy with Ragged Red Fibers (MERRF) syndrome is a mitochondrial encephalomyopathy linked to the mitochondrial A8344G DNA mutation.
  • Fibrous dysplasia of bone is a developmental disorder often associated with c-fos overexpression.

Observation:

  • A 10-year-old boy with MERRF syndrome and the A8344G mutation developed rapidly progressing visual disturbances.
  • Brain MRI revealed optic nerve compression due to sphenoid fibrous dysplasia, confirmed histologically.

Findings:

  • This study reports the first documented association between MERRF syndrome and fibrous dysplasia.
  • The mitochondrial A8344G mutation may influence c-fos expression, potentially contributing to fibrous dysplasia development.

Implications:

  • This rare co-occurrence may be underdiagnosed or coincidental.
  • Clinicians should consider skeletal system evaluation in MERRF patients exhibiting focal symptoms, particularly visual disturbances.

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