Case Files of the Harvard Medical Toxicology Fellowship at Children’s Hospital Boston: An Insulin Overdose

Abstract

A 16-year-old boy with a history of type I diabetes mellitus being managed with an insulin pump presented to the emergency department in cardiac arrest. Per report from the patient's mother, the patient had noticed that his insulin cartridge, containing insulin lispro, was empty the night prior to admission so he had replaced it at approximately 7:00 PM. He had used his glucometer through the night with recorded values of 225-389 mg/dL and had administered a total of 14.5 units of insulin via his pump. At around 6:30 AM, the morning of admission, his mother attempted to wake him for school and found him cyanotic and motionless. She attempted to obtain a fingerstick glucose measurement but was unable to do so and administered glucagon, as well as activating Emergency Medical Services (EMS). When EMS arrived, the patient was pulseless. Cardiopulmonary resuscitation was initiated, and the patient was endotracheally intubated. Point-of-care glucose determination was 81 mg/dL. He received epinephrine, atropine, naloxone, and an ampule of 50% dextrose (25 g) during his prehospital care. He was defibrillated twice at 200 J for ventricular fibrillation. He was transferred to the emergency department with cardiopulmonary resuscitation in progress. EMS reported that an empty insulin syringe had been seen underneath the patient's bed. After approximately 1 h of resuscitative efforts, during which the patient received additional epinephrine, sodium bicarbonate, and hydrocortisone, he had return of spontaneous circulation. His initial arterial blood gas revealed a pH of 6.8, PaCO 2 of 70 mmHg, and PaO 2 of 335 mmHg. His serum glucose at that time was 377 mg/dL, and the anion gap was 39 mEq/L with urine negative for ketones. He underwent computed tomography scan of the head, chest, abdomen, and pelvis that demonstrated left upper lobe consolidation and gastric distention but was otherwise normal. He was transferred to a tertiary-care children's hospital where his serum glucose on arrival was 50 mg/dL. He received 25 g of intravenous dextrose, and an infusion of 10% dextrose in normal saline was started. A toxicology consult was obtained.

Treatment of sulfonylurea and insulin overdose

“…Diabetics may present with symptoms at normal blood glucose if patients tend towards a high baseline, yet longstanding diabetics may have fewer symptoms due to weakened counter‐regulatory response . Diabetics with insulin insensitivity may have less glucose utilization for a given dose compared with non‐diabetics.…”

Factitious hypoglycemia in children and adolescents with diabetes

“…In youth with type 1 diabetes, its prevalence has been found as high as 1 in 7 youths, which is at least twice as high as in youths in general . Several cases of attempted or completed suicide with insulin overdoses have been reported in adolescents in whom no clear history of preceding factious hypoglycemia was known . One can only speculate that previous hypoglycemic episodes were also intentionally self‐induced and might have been a warning sign.…”

“…To be considered for this study, reports had to: (1) include subjects less than 18 years of age, (2) directly relate to individuals with diabetes (type 1 diabetes, type 2 diabetes, DIDMOAD [diabetes insipidus, diabetes mellitus, optic atrophy, and deafness] or Wolfram syndrome, mitochondrial, MODY [maturity onset diabetes of the young] or other), and (3) include intentional, self‐induced hypoglycemia. Cases of factitious hypoglycemia in patients without diabetes and cases of attempted or completed suicide associated with intentional overdosing (insulin or oral hypoglycemic agents) without a preceding history of factitious hypoglycemia were not included . From qualifying reports the following information was extracted: demographic characteristics, type and duration of diabetes, overall glycemic control, prescribed diabetes treatment, history of diabetic ketoacidosis (DKA), and the method of induction of factitious hypoglycemia, therapeutic intervention and long‐term follow‐up.…”

“…We performed a systematic review of the English literature through 17,18 and cases of attempted or completed suicide associated with intentional overdosing (insulin or oral hypoglycemic agents) without a preceding history of factitious hypoglycemia were not included. [19][20][21] From qualifying reports the following information was extracted: demographic characteristics, type and duration of diabetes, overall glycemic control, prescribed diabetes treatment, history of diabetic ketoacidosis (DKA), and the method of induction of factitious hypoglycemia, therapeutic intervention and long-term follow-up.…”

“…43 Several cases of attempted or completed suicide with insulin overdoses have been reported in adolescents in whom no clear history of preceding factious hypoglycemia was known. 20,21,[44][45][46] One can only speculate that previous hypoglycemic episodes were also intentionally self-induced and might have been a warning sign. A recent analysis documented excess all-cause mortality in young individuals (less than 30 years of age) with type 1 diabetes and found that the most common causes were ketoacidosis, likely hypoglycemia and suicide.…”