Diabetic Ketoacidosis Complicating Gestational Diabetes Mellitus

BACKGROUND/OBJECTIVE: The prevalence of diabetic ketoacidosis (DKA) in gestational diabetes mellitus (GDM) is very low. We describe a patient with GDM in whom severe DKA with intrauterine fetal demise developed in the setting of nonadherence to therapy. CASE REPORT: A 33-year-old woman, G2P0010, with no preexisting diabetes mellitus (DM) presented at 30 weeks of gestation with acute-onset altered sensorium, nausea, and emesis. GDM was diagnosed at 15 weeks of gestation with a serum glucose level of 266 mg/dL (70-134 mg/dL) after 1-hour 50-gram glucose challenge test. Glycated hemoglobin (HbA1C) was 5.9% (41 mmol/mol) at the time of GMD diagnosis. Insulin was initiated at week 20 of gestation. On presentation, serum glucose level of 920 mg/dL (70-110 mg/dL), pH of 7.02 (7.32-7.43), anion gap level of 38 mmol (5-17 mmol), bicarbonate level of 5.0 mEq/L (22-29 mEq/L), and large serum ketones were found. Ultrasound showed intrauterine fetal demise. She received intravenous fluids and continuous insulin. Following the spontaneous delivery of a nonviable fetus, DKA was resolved. Negative antiglutamic acid decarboxylase, islet cell, and zinc transporter 8 antibodies, C-peptide level of 2.4 ng/dL (1.1-4.4 ng/dL), and HbA1C level of 9% (75 mmol/mol) were found. Inpatient management included basal-bolus and sliding scale insulin therapies. Metformin was added upon discharge 7 days after admission. The HbA1C levels were 5.3% (34 mmol/mol) and 5% (31 mmol/mol) at the 3- and 6-month follow-ups, respectively. Insulin was discontinued. Currently, the patient is on metformin and glucagon-like peptide 1 receptor agonist. DISCUSSION: The development of insulin resistance during pregnancy is driven by multiple factors. Approximately 1% to 2% of pregnant women with impaired glucose tolerance develop DKA; most cases occur in women with type 1 DM. The approximate incidence of DKA in GDM is 0.02%. CONCLUSION: DKA complicating GDM is extremely infrequent, but it cannot be dismissed. Early recognition along with prompt and appropriate medical and obstetrical management is critical.