Severe Hypoglycemia in a Non-Diabetic Patient

Introduction: Accidental ingestion of insulin secretagogue may result in severe life-threatening hypoglycemia. Patients in long-term care may be especially vulnerable if proper medication administration safety guidelines are not followed. Case: A 62-year-old woman who was staying at a residential living facility (RLF) for the homeless, presented to the emergency room with altered mental status. Her past medical history included hypertension, COPD, psoriasis, and alcohol abuse. Prior to arriving to the emergency room, she was drinking alcohol excessively. Head CT results were normal. Capillary blood glucose (FBG) level was noted to 38 on EMS arrival. Her FBG improved to 69 after glucagon and her mental status improved shortly afterwards. ED was planning on discharging her when she became unresponsive with tonic-clonic seizure-like activity. The FBG at that time was 17. She was given Ativan and 10% Dextrose IV followed by 5% Dextrose Normal Saline (D5NS) drip. She recovered consciousness and was admitted for further monitoring. Endocrinology was consulted for hypoglycemia (HG). The patient denied prior diagnosis of diabetes mellitus or access to diabetic medications. Her medications were dispensed to her daily by staff at RLF. We held D5NS in order to perform testing for HG. Within 30 minutes she developed symptoms of HG. Hypoglycemic profile labs including C-peptide, insulin, beta-hydroxybutyrate, pro-insulin, hypoglycemic agent screen, insulin antibodies were drawn prior to reversal of HG. Laboratory findings: Venous BG - 26 mg/dL. Beta-hydroxybutyrate level (BHB) - 0.02 mmol/L (n, 0.02–0.27). The insulin antibody - 6.9 ng/mL (n, <5). C-peptide - 8.5 uU/mL (n, 1.1–4.4), insulin level - 53.2 uIU/mL (n, 2.6–24.9). Proinsulin - 8.6 pmol/L (n, <10.0). She had normal GFR of 95.94 mL/min/1.73m2 (n, >60) and elevated liver enzymes. Abdominal ultrasound results were consisted with cirrhosis. HG resolved after 36 hours. HG drug screen performed at Mayo Clinic lab by highly sensitive LC/MS/MS assay was positive for Glimepiride. Discussion: This case illustrates importance of high degree of suspicion for drug-induced HG in a patient presenting with profound HG and no previous history of diabetes. Discharging this patient prematurely could have resulted in hypoglycemic coma and death. Severity of HG was not consistent with alcoholism and cirrhosis. Suppressed BHB level coupled with high-normal pro-insulin and markedly elevated C-peptide and insulin levels were consistent with endogenous hyperinsulinemia. Sulfonylureas are known to have a long half-life; hypoglycemic effect can last for 12 to 24 hours or longer, especially in patients with impaired kidney or hepatic dysfunction. Since results of HG work-up are typically not available for several days, clinical observation and avoidance of premature discharge following initial reversal of HG are very important.