Hyponatremia In Children With Hydrocephalus

Abstract

Background: Hydrocephalus is a prevalent neurological condition in pediatric populations,  often leading to cognitive impairment and developmental delays. Hyponatremia is an electrolyte disturbance that can exacerbate neurological outcomes and can lead to severe complications, such as cerebral edema and seizures. Despite its clinical significance, there is limited data on the prevalence and severity of hyponatremia in children with hydrocephalus, particularly in resource-limited settings. This study aimed to determine the incidence of hyponatremia in children under 2 years with non-tumour hydrocephalus at Kenyatta National Hospital (KNH). Methods: A hospital-based prospective cohort study was conducted at KNH among 40 pediatric patients diagnosed with non-tumor hydrocephalus. Clinical assessments, serum  sodium, serum and urine osmolality, urine sodium, and radiological parameters (Evans Index)  were recorded. The type and severity of hyponatremia were classified based on standard biochemical criteria. Data were analyzed using SPSS, with Pearson correlations and Kruskal Wallis tests applied where appropriate. Results: True hyponatremia (serum sodium <135 mmol/L with low osmolality) was found in  70% of participants. Of these, 25% had mild, 22.5% moderate, and 22.5% severe hyponatremia. The Evans Index showed a significant inverse correlation with serum sodium levels (r = -0.472, p = 0.002), while head circumference Z-scores did not. Euvolemic hyponatremia and SIADH were the most common subtypes. Following ventriculoperitoneal shunting (VPS) in 34 patients, mean serum sodium improved by 8.6 mmol/L, although 50% remained hyponatremic post-operatively. Conclusion: Hyponatremia is a highly prevalent and clinically significant condition in pediatric patients with non-tumor hydrocephalus at KNH. Radiological ventricular dilation, as reflected by the Evans Index, correlates with hyponatremia severity. While surgical CSF diversion improves sodium balance in many cases, persistent hyponatremia remains common, necessitating continued biochemical monitoring and targeted management strategies.