A Japanese case of congenital hyperinsulinism with hyperammonemia due to a mutation in glutamate dehydrogenase

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Glutamine Flux Imaging Using Genetically Encoded Sensors
10:23

Glutamine Flux Imaging Using Genetically Encoded Sensors

Published on: July 31, 2014

K Yasuda1, N Koda, H Kadowaki

  • 1Institute for Diabetes Care and Research, Asahi Life Foundation, Department of Metabolic Diseases, Graduate School of Medicine, Universitiy of Tokyo.

Internal Medicine (Tokyo, Japan)
|February 24, 2001
PubMed

Insights

This study reports a Japanese infant with neonatal hyperinsulinism caused by a GLUD1 gene mutation. The condition led to severe hypoglycemia, hyperammonemia, seizures, and developmental delays.

Area of Science:

  • Genetics
  • Pediatrics
  • Endocrinology

Background:

  • Neonatal hyperinsulinism is a rare condition causing severe hypoglycemia in newborns.
  • Activating mutations in the glutamate dehydrogenase (GLUD1) gene are a known cause of congenital hyperinsulinism.

Observation:

  • A Japanese male infant presented with hypoglycemic coma and hyperinsulinemia shortly after birth.
  • The patient underwent subtotal pancreatectomy, revealing nesidioblastosis (an increase in endocrine cells).

Findings:

  • A de novo mutation (Gly446Asp) in the GLUD1 gene was identified as the cause.
  • The patient exhibited persistent hyperammonemia, seizures, and mental retardation, consistent with GLUD1-related disorders.
  • This case highlights GLUD1 mutations as a cause of congenital hyperinsulinism in the Japanese population.

Implications:

  • GLUD1 mutations should be considered in the genetic diagnosis of congenital hyperinsulinism, particularly in cases with hyperammonemia.
  • Understanding the genotype-phenotype correlation in GLUD1 mutations is crucial for patient management and prognosis.
  • This case contributes to the understanding of genetic causes of hyperinsulinism in diverse ethnic groups.

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