ABSTRACT
Neonatal diabetes mellitus (DM) is a persistent hyperglycemia occurring in the first 4-6 weeks of life that lasts more than two weeks and requires insulin for management. We report a case of a 23-day-old boy with neonatal diabetes due to recessive inheritance INS promoter C-331 C>A mutation accompanied by diabetic ketoacidosis (DKA). The hyperglycemia and ketoacidosis resolved by the 48th hour of treatment consisting of IV insulin and rehydration. Subsequently, insulin treatment was continued with neutral protamine Hagedorn (NPH) insulin. Neonatal DM due to genetic mutation may mimic sepsis and should be kept in mind for all newborns who present with shortness of breath, vomiting, and dehydration.