The Diagnosis of Neonatal Diabetes in a Mother at 25 Years of Age

Neonatal diabetes (ND) is defined as persistent hyperglycemia in the first 3 months of life (1). Heterozygous—usually autosomal-dominant—activating mutations in KCNJ11 , which encode the Kir6.2 subunit of the ATP-potassium (KATP) channel, cause the majority of cases (2). Sulfonylureas close the KATP channel by an ATP independent route (2). A 25-year-old Bangladeshi woman with type 1 diabetes gave birth to a baby girl. The mother had been on insulin for more than 20 years with inadequate glycemic control but never ketoacidosis. The baby was small for gestational age (2.4 kg, <3%). On day 2 of her life, the baby was noted to be increasingly hyperglycemic, reaching 312 mg/dL by day 7. Given the clinical suspicion for ND, a trial of glyburide was initiated at 0.45 mg/kg/day, and the baby responded well. The …