What is a characteristic of hypertonic hyponatremia?

Hypertonic hyponatremia occurs when there is an excess of osmotically active substances in the plasma, such as glucose, leading to a dilutional effect on sodium levels. In the case of hyperglycemia, for example, elevated glucose levels can draw water from the intracellular space into the intravascular space, resulting in dilution of sodium concentration despite the overall sodium level being decreased.

This dilution effect occurs because sodium is not the only solute in the plasma; as the osmolality increases due to hyperglycemia, the serum sodium may appear low when in fact the body may exhibit normal sodium but with higher osmotic pressure. Therefore, the characteristic interference from hyperglycemia emphasizes the dilutional nature of sodium levels seen in hypertonic hyponatremia, making this the correct choice in the context of this clinical scenario.

The other options, such as dehydration, increased blood sodium levels, and low urine sodium concentration, do not align with the pathophysiology of hypertonic hyponatremia. Dehydration typically leads to a different form of hyponatremia (hypovolemic), and low urine sodium levels often suggest a compensatory mechanism in response to volume depletion, which