ESPE Abstracts

Background: Several previous publications have documented the usefulness of Nifedipine for treating hyperinsulinaemic hypoglycaemia (HI). These reports include transient and persistent forms of HI, with and without known genetics, used in monotherapy or in combination with other drugs, and demonstrate various outcomes.

Objective and hypotheses: To systematically trial Nifedipine in children with known HI mutations and diazoxide unresponsive, assessing glycaemic control.

Method: Nifedipine was administered according to our hospital’s protocol for HI management. Two hourly blood glucose determinations were performed whilst on this medication. The dose of Nifedipine was withheld should the systolic blood pressure be under the 5th percentile for gender and age. Information regarding birth and HI presentation characteristics, family history, associated illnesses, genetic result, PET scan/histology report, surgery and other HI medication, and maximum dose of Nifedipine administered were collected.

Results: Ten patients were recruited (six females) with ages ranging from 1 month to 14 years. The genetics were: homozygous ABCC8, compound and paternally inherited heterozygous ABCC8, heterozygous KCNJ11 and paternally inherited GCK. All of them were diffuse HI disease. The median maximum dose of Nifedipine received was 2.5 mg/kg per day. Three subjects had Nifedipine in monotherapy, whilst four also received octreotide, one octreotide + glucagon, one octreotide + diazoxide and one octreotide + sirolimus. After a median of 7 days of trial none of the patient’s demonstrated improvement in glycaemic control, hence it was discontinued in all cases, and their blood glucose concentrations were subsequently stabilised with other medications.

Conclusion: Children with HI due to mutations in ABCC8, KCNJ11 and GCK genes do not respond to therapy with Nifedipine. This is the first study to systematically assess the effectiveness of Nifedipine in children with genetic causes of HI.