Abstract 121: Permanent neonatal diabetes mellitus due to KCNJ11 mutation: A case report

Introduction: Neonatal Diabetes mellitus in first 6 months of life is usually monogenic and is usually referred to as neonatal diabetes mellitus. The incidence of neonatal diabetes is extremely rare and varies from 1:89000 to 1:400000 live births. The most common cause of permanent neonatal diabetes is heterozygous activating mutation in the KCNJ11 gene encoding kir 6.2. Case Report: we report a 1 month 25 days male infant presented to our hospital with complaints of excessive inconsolable cry, up rolling of eyes, staring look, difficulty in breathing, refusal of feeds and repeated seizures, diagnosed outside as diabetic ketoacidosis (GRBS- 600 mg/dl, PH- 6.96, HCO3- 2.1, PCO2- 10) and managed accordingly with IV fluids, insulin and antiepileptic. Referred to our hospital for further management. On evaluation diagnosed as neonatal DM. 4th hourly GRBS was done and insulin Glargine given as basal regimen. Bolus doses of regular insulin was given based on GRBS. C peptide levels were low. Genetic study revealed heterozygous missense variation in exon1 of KCNJ11 gene (pArg201Cys). After genetic analysis baby was admitted to change over from insulin to sulfonylurea treatment. The patient was put on CGMS (Medtronic) on day2 of admission. Baby was started on Tab. Glibenclamide (0.1 mg/kg/dose) BD and gradually increased to 1 mg/kg/dose BD. Gradually regular insulin was tapered to 0.5 units sos and Inj. Glargine was reduced from 3 units BD to 0.5 units BD and blood sugars were under control. He was gradually transitioned from insulin to glibenclamide. He is presently 3.5 years with a weight of 12 kgs and height of 94.5 cms. He is presently in good glycaemic control, with the tablets being given twice a day. Conclusion: This genetic diagnosis has therapeutic implications as patients can switch from insulin therapy to sulphonylurea, as described in this case report. Most of the children with a KCNJ11 gene mutation have an overall good prognosis with good glycaemic control attained with oral sulphonylurea therapy.