What Is the Role of Vaptans in Routine Clinical Nephrology?

[摘要] Hyponatremia is the most common electrolyte disorder encountered in hospitalized patients, and both community- and hospital-associated hyponatremia are associated with in-hospital mortality and heightened resource consumption (1). As described by Wald et al. (1) in their evaluation of close to 100,000 hospitalizations during their 7-year study, it is not known whether hyponatremia is a marker of the severity of the underlying condition(s) or a direct contributor to the adverse outcomes observed. With the advent of vasopressin V2 receptor antagonists (termed vaptans) to treat hyponatremic patients, this important clinical question could be tested. The Study of Ascending Levels of Tolvaptan in Hyponatremia (SALT) studies have demonstrated that tolvaptan, an oral vasopressin V2 receptor antagonist, was effective in increasing serum sodium concentration at day 4 and day 30 (2). As a follow-up, 111 patients with hyponatremia received tolvaptan for a mean of 701 days, with maintenance of the increased serum sodium (3). These important studies included mildly symptomatic patients, but patients with a serum sodium <120 mmol/L in association with neurologic impairment were excluded. Vaptans are expensive drugs and their use in symptomatic patients has not been assessed. Vaptans seem to be as safe as urea according to Soupart et al. (7) in the present issue of CJASN, and urea is not expensive at all. The authors are suggesting that both vaptans and urea should be tested to decrease adverse outcomes in symptomatic and nonseverely symptomatic hyponatremic patients. Soupart et al. and Decaux et al. from two different hospitals in Belgium have been promoting the use of oral urea to treat patients with hyponatremia (4–7).

[学科分类] 泌尿医学

[关键词] Bone marrow necrosis;Sickle cell disease;Hyperhemolysis syndrome