CSWS Versus SIADH as the Probable Causes of Hyponatremia in Children With Acute CNS Disorders

OBJECTIVE: There is a major problem about the incidence, diagnosis, and differentiation of cerebral salt wasting syndrome (CSWS) and syndrome of inappropriate secretion of antidiuretic hormone (SIADH) in patients with acute central nervous system (CNS) disorders. According to rare reports of these cases, this study was performed in children with acute CNS disorders for diagnosis of CSWS versus SIADH. MATERIALS & METHODS: This prospective study was done on children with acute CNS disorders. The definition of CSWS was hyponatremia (serum sodium ≤130 mEq/L), urine volume output ≥3 ml/kg/hr, urine specific gravity ≥1020 and urinary sodium concentration ≥100 mEq/L. Also, patients with hyponatremia (serum sodium ≤130 mEq/L), urine output < 3 ml/kg/hr, urine specific gravity ≥1020, and urinary sodium concentration >20 mEq/L were considered to have SIADH. RESULTS: Out of 102 patients with acute CNS disorders, 62 (60.8%) children were male with mean age of 60.47±42.39 months. Among nine children with hyponatremia (serum sodium ≥130 mEq/L), 4 children had CSWS and 3 patients had SIADH. In 2 cases, the cause of hyponatremia was not determined. The mean day of hyponatremia after admission was 5.11±3.31 days. It was 5.25±2.75 and 5.66±7.23 days in children with CSWS and SIADH, respectively. Also, the urine sodium (mEq/L) was 190.5±73.3 and 58.7±43.8 in patients with CSWS and SIADH, respectively. CONCLUSION: According to the results of this study, the incidence of CSWS was more than SIADH in children with acute CNS disorders. So, more attention is needed to differentiate CSWS versus SIADH in order to their different management.