- Poster presentation
- Open Access
Long-term outcome of a child with hyperinsulinism- hyperammonaemia syndrome
© Yau and Wong; licensee BioMed Central Ltd. 2013
- Published: 3 October 2013
- Ammonia Level
- Blood Glucose Monitoring
Clinical features of hyperinsulinism-hyperammonaemia syndrome are variable. A potential genotype-phenotype correlation of GLUD1 mutation and clinical features has been suggested. We here report the long-term outcome of a child with hyperinsulinism-hyperammonaemia syndrome.
28 days of life
34 days of life
Plasma glucose (mmol/l)
Growth hormone (IU/l)
Workup for metabolic diseases was unremarkable. But ammonia levels were persistently high up to 252-353 umol/l. Octreotide injection was started to achieve euglycaemia. Protein free diet was tried but without success in lowering ammonia levels. Octreotide was later switched to oral diazoxide and hydrochlorothiazide. Full enteral feeding was established with stable glucose levels.
Genetic analysis showed a mutation in axon 10;Asn410I1e (N410I), a mutation of AAC to ATC at codon 410. The diagnosis of hyperinsulinism-hyperammonaemia syndrome was confirmed. We follow the child until he is 6 years of age. Home blood glucose monitoring prevented him from hypoglycaemia. Fasting test was performed every year to fine tune his diazoxide dosage. He remained seizure free while ammonia levels remained high up to 123-218 µmol/l. Formal developmental assessment performed at 5 years of age showed delay in cognitive and speech development for 1-1.5 years, and attention-deficit hyperactivity syndrome.
Clinical features of hyperinsulinism-hyperammonaemia syndrome are variable. A genotype-phenotype correlation requires confirmation in larger series of patients.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.