Sodium-glucose co-transporter-2 inhibitor-associated euglycemic diabetic ketoacidosis that prompted the diagnosis of fulminant type-1 diabetes: A case report

BACKGROUND: Fulminant type 1 diabetes mellitus (FT1DM) is a subtype of type 1 diabetes mellitus characterized by an abrupt onset and a rapid and complete functional loss of islet β cells. It is a very rare disease generally associated with ketoacidosis and the absence of circulating pancreatic islet-related autoantibodies. Diabetic ketoacidosis with normal blood glucose levels has been reported during sodium-glucose co-transporter 2 (SGLT2) inhibitor therapy. CASE SUMMARY: The patient was a 43-year-old woman that consulted a medical practitioner for malaise, thirst, and vomiting. Blood analysis showed high blood glucose levels (428 mg/dL), a mild increase of hemoglobin A1c (6.6%), and increased ketone bodies in urine. The patient was diagnosed with type 2 diabetes mellitus. The patient was initially treated with insulin, which was subsequently changed to an oral SGLT2 inhibitor. Antibodies to glutamic acid decarboxylase were negative. Four days after receiving oral SGLT2 inhibitor, she consulted at Mie University Hospital, complaining of fatigue and vomiting. Laboratory analysis revealed diabetic ketoacidosis with almost normal blood glucose levels. The endogenous insulin secretion was markedly low, and the serum levels of islet-related autoantibodies were undetectable. We made the diagnosis of FT1DM with concurrent SGLT2 inhibitor-associated euglycemic diabetic ketoacidosis. The patient's general condition improved after therapy with intravenous insulin and withdrawal of oral medication. She was discharged on day 14 with an indication of multiple daily insulin therapy. CONCLUSION: This patient is a rare case of FT1DM that developed SGLT2 inhibitor-associated diabetic ketoacidosis with almost normal blood glucose levels. This case report underscores the importance of considering the diagnosis of FT1DM in patients with negative circulating autoantibodies and a history of hyperglycemia that subsequently develop euglycemic diabetic ketoacidosis following treatment with a SGLT2 inhibitor.