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A neonatal form of glycogen storage disease type IV

M Nambu1, K Kawabe, T Fukuda

  • 1Department of Pediatrics, Tenri Hospital, Nara, Japan. nambum@tenriyorozu-hp.or.jp

Neurology
|August 13, 2003
PubMed

Insights

Neonatal glycogen storage disease type IV (GSD IV) in an infant presented with severe hypotonia and cardiomyopathy. Genetic analysis revealed a homozygous deletion in the GBE1 gene, confirming the diagnosis.

Area of Science:

  • Biochemistry
  • Genetics
  • Pediatric Medicine

Background:

  • Glycogen storage disease type IV (GSD IV) is a rare inherited metabolic disorder.
  • It is caused by deficiency of glycogen branching enzyme (GBE1), leading to abnormal glycogen accumulation.
  • Neonatal onset GSD IV is typically severe and rapidly progressive.

Observation:

  • An infant presented with severe hypotonia and cardiomyopathy.
  • Muscle biopsy revealed numerous diastase-resistant polyglucosan bodies within muscle fibers.
  • Markedly reduced glycogen branching enzyme (GBE1) activity was detected in muscle tissue.

Findings:

  • The infant harbored a homozygous single nucleotide deletion in the open reading frame of the GBE1 gene.
  • This genetic mutation directly explains the observed GBE1 deficiency and polyglucosan accumulation.
  • The findings confirm the molecular basis of GSD IV in this patient.

Implications:

  • This case highlights the importance of early GBE1 gene analysis in infants with GSD IV symptoms.
  • Understanding the specific mutation provides insight into disease pathogenesis.
  • Further research into GBE1 mutations can aid in diagnosis and potential therapeutic strategies for GSD IV.

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