Neonatal Diabetic Ketoacidosis - A Case Report

Background: Neonatal diabetes mellitus (NDM) is a rare condition (1 in 400,000 live births). It generally presents within the first 6 months of life and may be transient or permanent. The transient form is commonly associated with paternal isodisomy and monogenic variants, such as KCNJ11 and ABCC8, located on chromosome 6. The permanent form is also associated with monogenic variants, most commonly KCNJ11 and ABCC8. Diabetic ketoacidosis (DKA), which is common in older children and teens with autoimmune diabetes mellitus (T1D), is rare in NDM and often overlooked. Case Study: A 1-day-old female with low birthweight (2.520 kg) was referred to Cook Children’s Medical Center for tachypnea (78 to 84 bpm) and hyperglycemia. Her blood pH was 7.22 (7.29 – 7.24), pCO2 <12 (27- 40 mmHg), pO2 122 (54-95 mmHg), and HCO3 of 4.1 (19.0-24.0 mmol/L). Blood glucose levels were >200 mg/dL. Due to persistent respiratory symptoms, she was suspected of being septic and was treated with ampicillin and gentamicin. She was on the cutoff for SGA. Within the initial 48 hours of admission, her lab test results were consistent with DKA - blood glucose of 305 mg/dL (50-96 normal), lactic acid of 2.3 mmol/L (0.5-2.0 normal), anion gap of 21 (10-16 normal) and B-hydroxybutyrate of 9 mmol/L (0.4-0.5 normal). Genetic testing showed a variant of unknown significance in HNF1a. Following stabilization, the parents underwent diabetes education, and the infant was discharged on daily insulin therapy for follow-up in the Endocrine clinic. By 5 years-of-age, she continued to require daily injections of insulin for glucose control. This case is unique in that the infant was found to have a variant of unknown significance for HNF1a, a monogenic mutation that is typically seen in maturity-onset diabetes of the young (MODY). In general, MODY is not typically associated with DKA. Therefore, while our finding is intriguing, we cannot state that this variant is causative in the case we presented. Further reports of HNF1 variants are needed to help determine if there is an association with NDM and DKA. Conclusions: In infants, NDM and DKA are rare and present with nonspecific symptoms, which often delays the diagnosis. Although rare, it is imperative that NDM and DKA be considered in order to avoid adverse consequences, including death.