Context: Neonatal diabetes is a rare disorder with an incidence of about 1 in 100,000 live births. It is defined as diabetes diagnosed in the first 6 months of life and it is vital to differentiate this entity from type 1 diabetes to enable accurate diagnosis, prognosis, genetic counseling and treatment.
Case report: We describe a case of permanent neonatal diabetes mellitus due to a novel mutation affecting the ABCC8 gene that encodes the SUR1 subunit of potassium ATP channel (KATP).
Conclusion: This genetic diagnosis has therapeutic implications as patients can switch from insulin therapy to sulphonylurea, as described in this case report.