ABCC8-related maturity-onset diabetes of the young: switching from insulin to sulphonylurea therapy: how long do we need for a good metabolic control?

Objectives: Activating variants of the ABCC8 gene cause neonatal diabetes or maturity-onset diabetes of the young (MODY). We report three cases of MODY type 12 caused by variants in the ABCC8 encoding sulphonylurea receptor 1, and the experience of switching from insulin therapy to sulphonylurea therapy.Case presentations: We describe a 12.5-year-old girl with permanent neonatal diabetes mellitus, and two diabetes mellitus cases with variants in the ABCC8 gene. Two of these cases were successfully switched from subcutaneous insulin to oral glibenclamide, with a marked improvement in glycemic control. In permanent neonatal diabetes case, glibenclamide dose was progressively increased to achieve a full dose (2 mg/kg/day) in 9 days. Nine months after starting oral sulphonylurea therapy, her blood glucose control dramatically improved and insulin therapy was discontinued.Conclusions: We conclude that patients with ABCC8 gene variants can successfully switch from insulin to sulphonylureas.