[Hyperosmolar Hyperglycemic State (HHS) with extreme hyperglycemia and hyperglycemia-induced hyponatremia in a patient with previously known diabetes mellitus type 2].

This case report covers a patient presenting unconscious to the emergency department with a serum glucose level of 125.6 mmol/L and an associated hyperglycemia-induced hyponatremia with a sodium level of 101 mmol/L. The glucose level is, to our knowledge, one of the most extreme values described in medical literature. Glucose and sodium levels were normalized following treatment with intravenous fluids, mainly Ringer's lactate solution and insulin infusion with an initial rate of 0,5 IU/kg/h. The patient needed ten days of hospital care, including five days at the intensive care unit. Shortly after discharge the patient had a complete recovery. However, the extreme values led to difficulties regarding correction rates, choice of treatment and monitoring, which is further discussed in the article.