A 72-year-old patient with known type 2 diabetes on glyburide has a few days of fever, sore throat, and excessive urination, followed by lethargy. The patient is most likely experiencing which condition?

• A. Diabetic ketoacidosis
• B. Nonketotic hyperglycemic hyperosmolar state
• C. Hypoglycemia secondary to refusal to eat
• D. Lactic acidosis secondary to infection

Answer: (B)

This presentation fits nonketotic hyperosmolar hyperglycemic state, often triggered by infection in an older patient with type 2 diabetes. In NKHHS, severe hyperglycemia leads to profound osmotic diuresis and dehydration, which raises serum osmolarity and produces mental status changes like lethargy. Because there is still some endogenous insulin, lipolysis and ketone production are limited, so there is little to no ketoacidosis. The combination of polyuria, infection precipitant, and cognitive slowing without marked acidosis is the hallmark. This differs from diabetic ketoacidosis, which features significant ketosis and acidosis; hypoglycemia, which would present with low glucose and adrenergic symptoms; and lactic acidosis, which centers on metabolic acidosis from elevated lactate rather than extreme hyperglycemia with high osmolarity.