Protein causes hyperinsulinemia: A chinese patient with hyperinsulinism/hyperammonaemia syndrome due to a glutamate dehydrogenase gene mutation

Abstract

Glucose is derived from three sources: intestinal absorption, glycogenolysis, and gluconeogenesis. Hypoglycemia in child is often attributed to depletion of glycogen stores. However, recently, congenital hyperinsulinism becomes an important cause of hypoglycaemia in early infancy. Mutations in the genes encoding SUR1 and KIR6.2 are the most frequent genetic causes of hyperinsulinism followed by mutations in the glutamate dehydrogenase (GDH) gene which encodes hyperinsulinism/hyperammonaemia (HI/HA) syndrome.1 HI/HA syndrome was first reported by Zammarchi et al2 in 1996. In 1998, Stanley et al3 found that the mutations in the GDH gene are the reason of HI/HA syndrome. Here we describe a boy with a severe form of HI/HA syndrome with a GDH gene mutation, which had never been reported in China before, and evaluated the efficacy of oral carbohydrateprotein-adipose tolerance test in the diagnosis. We also designed a test to choose a proper ratio between carbohydrate and protein in its treatment, whereas six-month follow-up showed that dietary therapy could be a useful treatment.