Perioperative glycemic challenges during cesarean delivery in a parturient with insulin autoimmune syndrome (Hirata’s disease)

Sir,Insulin autoimmune syndrome (IAS), also known as Hirata’s disease, is a rare cause of endogenous hyperinsulinemic hypoglycemia characterized by the presence of insulin autoantibodies. The occurrence of IAS during pregnancy is exceedingly uncommon, and its coexistence with type 1 diabetes mellitus poses significant perioperative glycemic challenges due to unpredictable insulin–antibody interactions. We report the anesthetic management of a parturient with type 1 diabetes mellitus complicated by IAS undergoing elective cesarean delivery, highlighting the importance of meticulous perioperative glucose control. A 28-year-old primigravida at 37+ weeks of gestation with a known history of type 1 diabetes mellitus was diagnosed with IAS following recurrent unexplained hypoglycemic episodes. After a multidisciplinary discussion involving anesthesiology, obstetrics, and endocrinology teams, an elective cesarean section was planned. In the operating theater, standard American Society of Anesthesiologists monitoring was instituted along with left uterine displacement. Baseline capillary blood glucose was 104 mg/dL. Considering the risk of masked hypoglycemia and exaggerated stress response, spinal anesthesia was preferred. Subarachnoid block was administered at the L3–L4 interspace using 1.8 mL of 0.5% hyperbaric bupivacaine combined with fentanyl 20μg. Intraoperative blood glucose monitoring was performed every 10 min. A continuous infusion of 10% dextrose at 50 mL/h was maintained. No intraoperative insulin was administered. Blood glucose values ranged between 66 and 124 mg/dL. Two episodes of hypoglycemia were promptly treated with 25% dextrose boluses. Delivery was achieved within 8 min of skin incision. A healthy male neonate weighing 3.0 kg was delivered with Apgar scores of 8 and 9 at 1 and 5 min, respectively. Maternal hemodynamics remainedstable, and hypotension episodes were managed with phenylephrine boluses. Postoperatively, the patient was monitored in a high-dependency unit. Dextrose infusion was continued for 12 h with hourly glucose monitoring initially, followed by 4-hourly measurements. Low-dose insulin therapy was restarted under endocrinology guidance. No further hypoglycemic episodes were observed, and the postoperative course was uneventful. IAS complicating type 1 diabetes represents a rare and high-risk metabolic scenario. The binding ofcirculating insulin by autoantibodies leads to delayed and unpredictable insulin release, resulting in recurrent hypoglycemia. Pregnancy further compounds metabolic instability due to altered insulin sensitivity and hormonal fluctuations. Anesthetic management in such patients should focus on maintaining euglycemia during fasting and surgical stress, avoiding triggering medications, and ensuring frequent glucose monitoring. Regional anesthesia offers advantages by attenuating the neuroendocrine stress response and allowing early recognition of hypoglycemic symptoms. This case highlights that spinal anesthesia can be safely administered in parturients with IAS when meticulous perioperative planning and close multidisciplinary coordination are ensured.