Background: Congenital hyperinsulinism (CHI), a clinically and genetically heterogeneous disease, is the most common cause of persistent hypoglycaemia in infancy.
Case presentation: Here we describe an Egyptian male neonate first order of birth born to non-consanguineous healthy parents. At day 1 of age he presented with severe hypoglycemia and generalised seizures. At the time of hypoglycaemia (16 mg/dl) insulin and C-peptide levels were increased (insulin 72 (625 μIU/ml; C-peptide 7.8 (1.13.3 ng/ml), leading to the diagnosis of hyperinsulinaemic hypoglycaemia (HH). Serum GH, cortisol, ammonia, and lactate were normal. Patient was given glucose infusions and regular feeding hourly to maintain normoglycaemia. The patient was discharged and an out-patient follow-up was instituted without any treatment. However, recurrent episodes of hypoglycemia were noticed. Medications (hydrocortisone and nifedipine) had no substantial effect on glycemic profile. Another treatment was started on diazoxide 10 mg/kg per day with increasing dosage up to 25 mg/kg per day. This treatment was not effective and repeated episodes of hypoglycemia were observed two to three times a day. As parents refused surgery, Hydrochlorothiazide was added with substantial improvement of glycemic level. The child now is 1 year old growing well with no neurodevelopmental delay. Sequence analysis has identified a novel heterozygous missense mutation, p.E1517G (c.4550A>G) of the ABCC8 gene inherited form the father. As the p.E1517G mutation has been paternally inherited a focal lesion is possible, no mutation was identified in the mother.
Conclusion: Heterozygous paternally inherited ABCC8 mutations can lead to CHI which was responsive to medical treatment alone.
01 - 03 Oct 2015
European Society for Paediatric Endocrinology