Early-Onset Euglycemic Diabetic Ketoacidosis Following Empagliflozin Initiation Triggered by Acute Influenza and a Ketogenic Diet.

Euglycemic diabetic ketoacidosis (euDKA) is a form of diabetic ketoacidosis in which severe ketosis and acidemia occur despite mild hyperglycemia, leading to delayed diagnosis. EuDKA incidence has increased with widespread sodium-glucose cotransporter-2 inhibitor (SGLT2i) use, particularly during acute illness. While most reported cases occur after prolonged SGLT2i exposure, early-onset euDKA shortly after initiation remains rare. This case illustrates euDKA occurring within 48-72 hours of empagliflozin initiation in the setting of influenza A infection and a ketogenic diet, highlighting multifactorial euDKA pathogenesis and the need to reassess diabetes phenotype when insulin requirements are unexpectedly low. A 52-year-old female with type 2 diabetes mellitus presented with three days of flu-like symptoms, nausea, vomiting, dizziness, and poor oral intake. She initiated a ketogenic diet and empagliflozin 72 hours prior. Laboratory evaluation indicated high-anion-gap metabolic acidosis with a venous pH of 7.03, bicarbonate of 5 mmol/L, anion gap of 29, β-hydroxybutyrate of 7.0 mmol/L, and hyperglycemia (blood glucose 238 mg/dL). HbA1c was 10.6% (11.8% one month prior). She was admitted to the ICU and treated with fluids, insulin, and electrolyte monitoring. Despite severe acidemia, insulin requirements were minimal, totaling approximately 13.5 units, and she was transitioned to 5 units of glargine daily. Evaluation for autoimmune diabetes demonstrated preserved C-peptide (1.7 ng/mL) with negative glutamic acid decarboxylase-65 and islet cell antibodies. Adults presenting with ketoacidosis and low insulin requirements should prompt reassessment of diabetes phenotype when features are inconsistent with insulin-resistant type 2 diabetes. Continued SGLT2i therapy should be reconsidered to prevent recurrent metabolic decompensation.