ABSTRACT
Hyperinsulinism-hyperammonemia syndrome is characterized by recurrent and symptomatic hypoglycemias in childhood, secondary to hyperinsulinism associated with mild and asymptomatic hyperammonemia. This syndrome is caused by dominantly expressed mutations of the glutamate dehydrogenase gene (10q23.3). These mutations modify control of enzyme activity and represent the second cause of congenital hyperinsulinism of known genetic etiology. Moreover, this syndrome is the first genetic disorder due to an increase of function in an enzyme of intermediary metabolism to have been identified. We present the case of a 16-month-old boy with symptomatic recurrent hypoglycemias from the end of the first year of life, caused by a de novo mutation in exon 7 (G979A) of the GDH gene, with excellent outcome after diazoxide treatment.
Subject(s)
Diazoxide/therapeutic use , Glutamate Dehydrogenase/genetics , Hyperammonemia/drug therapy , Hyperammonemia/genetics , Hyperinsulinism/drug therapy , Hyperinsulinism/genetics , Mutation , Humans , Infant , Male , SyndromeABSTRACT
El síndrome de hiperinsulinismo-hiperamoniemia se caracteriza por hipoglucemias sintomáticas recurrentes en la infancia, secundarias a hiperinsulinismo, asociadas a un moderado y asintomático incremento de la amoniemia. Es debido a mutaciones en el gen de la glutamato deshidrogenasa (10q23.3), transmitidas de forma dominante, que alteran el control de la actividad enzimática y representa la segunda causa de hiperinsulinismo congénito de base conocida, siendo la primera enfermedad genética identificada debida a un aumento de la actividad de una enzima del metabolismo intermediario. Presentamos el caso de un niño de 16 meses con hipoglucemias sintomáticas recurrentes desde el final del primer año de vida, debidas a una mutación activadora de novo en el exón 7 (G979A) del gen de la GDH, con excelente respuesta terapéutica a diazóxido (AU)
