What is a common cause of hypervolemic, hypotonic hyponatremia?

Hypervolemic, hypotonic hyponatremia occurs when there is an excess of total body water relative to sodium, resulting in diluted serum sodium levels. A common cause of this condition is edema, which often arises in the context of heart failure, liver cirrhosis, or nephrotic syndrome. In these scenarios, the body retains water due to various compensatory mechanisms that aim to maintain blood volume and pressure, leading to increased extracellular fluid and consequent edema.

Edema reflects the fluid overload present in these patients and signifies that while total body sodium may be elevated or normal, the sodium concentration becomes diluted due to the excess fluid. This dilution is what characterizes hypotonic hyponatremia.

Other options, while related, do not directly lead to hypervolemic, hypotonic hyponatremia. For instance, low sodium intake generally causes hyponatremia in a normovolemic or hypovolemic state rather than hypervolemia. Hyperglycemia can cause a shift in fluid that affects sodium levels but does not typically present as hypervolemic. Renal salt wasting usually results in a decrease in both sodium and water retention, leaning towards hypovolemic hypon