BSPED2016 Oral Communications Oral Communications 6- Endocrine (9 abstracts)
1Great Ormond Street Hospital, London, UK; 2Institute of Child Health, London, UK.
Introduction: Several previous case reports have described the use of the calcium-blocker Nifedipine for the treatment of hyperinsulinaemic hypoglycaemia (HH). These cases are a collection of transient/permanent forms of HH, with known/unknown genetics, where Nifedipine has been used either as monotherapy or in combination with other medications. There have been no previous reports of any systematic trial of Nifedipine use in patients with HH due to mutations in the ABCC8 gene.
Methods: Prospective study assessing the glycaemic response to Nifedipine in children with HH due to mutations in ABCC8 gene and diazoxide-unresponsiveness. Nifedipine was administered at a starting dose of 0.25 mg/kg/day and increased to a maximum dose of 2.5 mg/kg/day. The information collected included family history and HH history (presentation, genetics, histology/18F-DOPA PET scan).
Results: In total of 11 patients (6 females) were trialled on Nifedipine at a median age of 0.44 years (range 0.143.77). The genetic mutations in ABCC8 gene were: homozygous in 3 cases, paternally inherited heterozygous in 4 and compound heterozygous in 4. 18F-DOPA PET scan demonstrated a focal lesion in 2 cases and the rest were diffuse HH disease. 1 subject had Nifedipine in monotherapy, whilst the rest had it in combination with octreotide/glucagon/diazoxide or cornstarch. After a median of 6.5 (323) days of maximal (2.5 mg/kg/day) of Nifedipine therapy none of the patients showed any improvement in glycaemic control and patients continued to have hypoglycaemic episodes.
Conclusion: Nifedipine therapy is in ineffective in patients with HH due to mutation in the ABCC8 gene.