Abstract
Diabetic ketoacidosis (DKA) may be complicated by acute kidney injury (AKI). While the pharmacokinetics of insulin degludec were previously suggested to be stable even in chronic kidney disease, its safety profile in acute or dynamic renal dysfunction remains unclear. We herein report a 13-yr-old boy with severe DKA complicated by AKI, who developed prolonged hypoglycemia after switching from continuous intravenous regular insulin to subcutaneous insulin aspart and insulin degludec. Insulin degludec was initiated, although the patient was no longer acidotic, during a period when his serum creatinine level was still rising. The patient repeatedly became hypoglycemic, which required the interruption of basal insulin for 8 d. In retrospect, the decision to initiate long-acting insulin during AKI was made in accordance with standard DKA protocols, without sufficient consideration of the deteriorated clearance of insulin degludec under impaired renal function. This case highlights the need for caution when initiating long-acting insulin analogues in patients with AKI, even in the post-DKA phase. Further studies are needed to elucidate insulin pharmacokinetics during non-steady-state renal impairment.