Rebound ketoacidosis in a patient with diabetic ketoacidosis using ultra-long-acting insulin

A 26-year-old Taiwanese woman with type 1 diabetes mellitus developed diabetic ketoacidosis after missing a premixed insulin dose. The case is notable for recurrent ketosis and hyperglycemia despite a 6-h overlap during the transition from intravenous to subcutaneous insulin therapy. The objective of this report is to describe the challenges of transitioning insulin regimens with ultra-long-acting insulin. A 26-year-old woman presented with severe diabetic ketoacidosis, confirmed by laboratory findings of blood glucose at 520 mg/dL, pH 7.14, bicarbonate 8 mmol/L, and serum ketones 5.9 mmol/L. She received intravenous insulin for 48 hours before transitioning to subcutaneous IGlar-300 with a 6-h overlap. Despite initial improvement, ketones rebounded to 4.2 mmol/L with hyperglycemia 7 hours after intravenous insulin discontinuation. Reintroduction of intravenous insulin for 48 hours and subsequent doses of IGlar-300 stabilized her condition, allowing discharge with resolved ketosis and improved glycemic control. This case underscores the challenges of transitioning to ultra-long-acting insulin during management of diabetic ketoacidosis. The pharmacokinetics of basal insulin analogs like IGlar-300 may necessitate extended overlap with intravenous insulin to maintain stable glycemic control and prevent rebound ketosis. This case highlights the need for careful management during the transition from intravenous to subcutaneous ultra-long-acting insulin to prevent rebound ketosis. Although not specifically addressed in current guidelines, an extended overlap with intravenous insulin may be required in similar cases. This case underscores the importance of tailored DKA management when using ultra-long-acting insulins , highlighting the need for extended overlap durations to ensure ketone clearance and avoid rebound ketoacidosis. • IGlar-300 requires longer overlap when switching from IV to SC insulin in DKA due to delayed onset.