Endocrine Abstracts

Intentional insulin overdose in diabetic patients is a rare critical situation. The severity is due to numerous neurological complications, electrolyte disturbances, liver and lung damage or death.

A 76-years old female, with significant cardiac pathology, diagnosed with type 2 diabetes and treated with Humalog Mix50^® 0-0-24 U/day, is admitted to our center via ER (emergency room) after an episode of severe hypoglycemia after administration of 1500U Humalog Mix50. She arrived in the ER one hour after the overdose with a glycemic value of 111 mg/dl after 50 ml of glucose 33% and 500 ml 10% glucose. At admission: altered general status, profuse sweating, multiple injection sites across her abdomen and thighs. Labs exams revealed: hypocalcaemia, hypokalemia, slightly elevated creatinine and BUN, mild normochromic, normocytic anemia, A1c=6.29%. An infusion of 10% glucose was begun at 1 L/h. The glucose infusion rhythm and concentration was adjusted according to the glycemic profile with a total duration of infusion of 46 h. Besides, multiple boluses of glucose 33% were needed to avoid the hypoglycemic events. Hypocalcaemia and hypokalemia were corrected by intravenous (i.v.) administration of calcium gluconate and potassium chloride. Psychological evaluation diagnosed depression and recommended a psychiatric consult. On day 3 since admission, the patient’s general condition worsened significantly with severe hypotension (requiring continuous positive inotropic infusion), liver and renal failure and she was transferred to the ICU. Despite intensive care maneuvers, the patient died of cardiac arrest through electromechanical dissociation.

Insulin overdose requires intensive and prolonged glycemic monitoring to prevent recurrent hypoglycemia. The dose is correlated with a prolonged hypoglycemic risk higher than that deduced from the pharmacokinetics of insulin administered. To our knowledge this case represents the largest overdose with Humalog Mix50^® ever reported.