Hyponatremia in cirrhosis: Evaluation and treatment

Abstract

Hyponatremia is a common complication in patients with cirrhosis that is related to impairment in the renal capacity to eliminate solute-free water. The main pathogenic factor associated with hyponatremia is a non-osmotic hypersecretion of vasopressin which acts in the V2-receptors in the renal collecting ducts. A decrease in serum sodium concentration is associated with an increased risk of hepatic encephalopathy. Hyponatremia is associated with poor prognosis in patients with cirrhosis. There is evidence that hyponatremia also represents a risk factor for liver transplantation, as it is associated with an increased frequency of complications and a decreased short-term survival after transplantation. Classical treatment of hyponatremia is based on fluid restriction, but is poorly effective. The current pharmacological approach to hyponatremia has advanced with vaptans, a new family of drugs which antagonize V2-receptors in the renal collecting ducts. Short-term treatment with vaptans is associated with an increase in serum sodium concentration and improvement in health-related quality of life. Nevertheless, information on the use of vaptans in cirrhosis is limited and further long-term studies are needed.