SEARCH

SEARCH BY CITATION

Sirs,

We read the study of Dahl et al. with great interest and congratulate the authors on this excellent piece of work.[1] The authors found that vaptans increased serum sodium levels and lead to reductions in weight, but these treatment increased the risk of adverse events in patients with cirrhosis and hyponatremia.

Hyponatraemia is a common problem in patient with advanced cirrhosis and ascites. In these patients, hyponatraemia occurs chronically and sodium levels drop gradually over several weeks. The degree of hyponatraemia often correlates with the severity of the underlying condition and therefore it is an important prognostic factor. So, therapy should be directed at the underlying disease. More aggressive therapy is indicated in patients who have symptomatic or severe hyponatraemia, and treatment should include restriction of sodium and water intake.[2, 3]

The vasopressin receptor antagonists, vaptans, produce a selective water diuresis without affecting sodium and potassium excretion. In patients with advanced cirrhosis and ascites, hypervolaemic hyponatraemia occurs as a result of a decrease in effective circulating volume (ECV).[4] The ensuing loss of free water will tend to cause a further reduction in ECV. This situation will cause systemic vasoconstriction, decreased renal blood flow and granular filtration fraction, and sodium and water reabsorption due to an over-active renin–angiotensin–aldosterone system. Thus, patients are locked in a vicious cycle of hyponatraemia and ascites.

Deleterious effects on ECV and other adverse effects of vaptans may restrict the use of these agents in patient with advanced cirrhosis. However, short-term use of vaptan with colloid oncotic pressure extenders would be more beneficial than other diüretics in the treatment of acute exacerbation of ascites.

Acknowledgement

  1. Top of page
  2. Acknowledgement
  3. References

Declaration of personal and funding interests: None.

References

  1. Top of page
  2. Acknowledgement
  3. References