Relationship between serum sodium level and severity of bronchiolitis in children hospitalized in Amirkola Children's Hospital

Despite the self-limiting nature of bronchiolitis, its severe forms require hospitalization. Electrolyte imbalance during bronchiolitis is common, however, the relationship between bronchiolitis severity and serum sodium (Na) levels has not been well studied. The purpose of this study was to investigate the relationship between serum Na level and bronchiolitis severity.

This cross-sectional study included hospitalized children with bronchiolitis at Amirkola Children’s Hospital, Babol, Iran, from May 2020 to May 2021. Diarrhea, underlying disease, glucocorticoid intake, and intravenous fluid therapy before admission were considered exclusion criteria. The Bierman-Pierson scale was used to evaluate the severity of the disease, and hyponatremia was divided into mild, moderate, and severe groups. Variables were analyzed using Statistical Packages for Social Sciences (SPSS) 26. A value of P<0.05 was considered significant.

Sixty-one children (55.7% male) with a mean age of 5.19 ± 4.36 months were enrolled in the study, with most (50.8%) belonging to the mild form of the disease. The mean serum Na levels based on the severity of bronchiolitis were 136.22 (SD: 2.99), 133.76 (SD: 3.88), and 130.50 (SD: 11.45) in the mild, moderate, and severe groups, respectively. There was a statistically significant relationship between serum sodium level and severity of bronchiolitis (P-value = 0.013).

The results showed that higher severity of bronchiolitis was associated with an increased risk of hyponatremia. Therefore, periodic monitoring and correction of hyponatremia in children with bronchiolitis, especially at younger ages, is necessary to improve the outcome of the disease.