Which electrolyte imbalance is characterized by symptoms of fluid overload?

Hyponatremia is characterized by low sodium levels in the blood, which can lead to a state of fluid overload in the body's cells. This condition occurs because sodium is essential for maintaining the balance of fluids in and around cells. When sodium levels drop, water can move into the cells to try to equalize the concentration gradient, causing them to swell. Symptoms of fluid overload can manifest as edema, nausea, headache, confusion, and in severe cases, seizures or coma due to increased intracranial pressure.

In cases of hyponatremia, the body attempts to compensate for the low sodium levels by reducing urine output and retaining water, further exacerbating fluid overload. This is in contrast to other electrolyte imbalances, such as hypokalemia, hypernatremia, and hypocalcemia, which do not typically lead to the same fluid retention and overload symptoms. Therefore, understanding the role of sodium in fluid balance is crucial in recognizing why hyponatremia is associated with symptoms of fluid overload.