Abstract
A 62-year-old man was being treated for type 2 diabetes mellitus. He accidentally subcutaneously injected himself with approximately 260 U of insulin glargine. Continuous intravenous infusion of glucose for 42 hours was thus required to prevent the onset of hypoglycemic episodes. Blood tests at the time of admission revealed hypoglycemia and hypo-osmotic hyponatremia, and a correction was immediately begun. The time course of the level of serum insulin analogue was measured and peaked 32 hours after arrival. He demonstrated dysphagia, dysarthria, and mild paresis in the left leg after he recovered from hypoglycemia and hyponatremia. Severe hypoglycemia may cause neurological disturbances that can cause central pontine myelinolysis (CPM). Although MRI did not show any features consistent with CPM in this case, his symptoms were similar to CPM and gradually improved. Previous reports suggest that his symptoms may have been caused by brain edema secondary to the failure of ion pumps in the cell membrane, due to glucose deprivation, and also possibly by brain edema from the large osmotic change. Appropriate management to correct hypoglycemia, fluid replacement and electrolyte balance are required when treating patients presenting with severe prolonged hypoglycemia and hypo-osmotic hyponatremia.
