Diagnosis and management of cerebral salt wasting (CSW) in children: the role of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP)

Abstract

Objective: The aim of this study is to report our experience with diagnosis and management of cerebral salt wasting (CSW) in children and to evaluate the role of atrial natriuretic peptide/brain natriuretic peptide (ANP/BNP) in pediatric patients.

Materials and methods: We present nine children suffering from prevalent cerebral disease--seven of whom underwent anesthesia and surgical procedures--with features of CSW, seen within a 22-month period. The symptoms, patient characteristics (including hormone status), monitoring, treatment protocol, and outcome are described.

Results: Natriuresis (urine Na+ concentrations 131 to >250 mmol/l) and polyuria (5.5+/-1.5 ml/kg/h) with increased Na+ turnover (maximum Na+ loss: median 1.50 mmol Na+/kg/h, range 0.47 to >3.50) vanished within 2 weeks in 6/9 patients (increase in serum Na+ from 127+/-2 mmol/l to 136+/-1). K+ excretion was also high (maximum K+ loss: median 0.18 mmol K+/kg/h, range 0.09-0.53). ANP/BNP as suspected causes of salt wasting were elevated only in 1/6 and 2/7 patients, respectively. Plasma renin activities and aldosterone levels were either suppressed or in the low normal range.

Conclusion: Natriuresis and polyuria are the main diagnostic criteria for CSW. The fluid balance in CSW is negative, in contrast to a positive fluid balance in SIADH. The length of the disease is self-limited and generally ceases within 2 weeks, while Na+, K+, and fluid turnover should be monitored carefully. Only a minority of our children showed elevated ANP/BNP levels. A dose/effect relationship for natriuretic peptide levels and increased Na+ turnover could not be established.