The serum sodium levels and recurrence of simple febrile seizure during the first 24 hours in children

Background: Febrile seizure (FS) is one of the most common neurologic disorders in children. Electrolyte imbalance especially hyponatremia may have an important role in triggering the febrile seizure. The measure of serum electrolytes will be useful in predicting the further seizure. The aim of this study was to investigate the effect of relative hyponatremia (RH) on the risk of recurrent febrile seizures. Methods: This prospective study was performed on 334 children (6-60-month) with convulsions, referred to Amirkola children's Hospital. The patients were divided into three groups: simple febrile seizure (SFS), complex febrile seizure (CFS) and seizure without fever. In each group, the serum sodium was measured at the beginning of the admission and followed for 24 hours, and electrolyte imbalance was evaluated in seizure recurrences. Data were analyzed using SPSS-16 (student's t-test and logistic regression). Results: Of the 334 children, 105 (31.7%) and 229 (68.3%) patients were female and male, respectively. The mean serum sodium levels in patients with SFS, CFS and control group were 136.64, 134.91 and 137.38 meq/l, respectively (p<0.05), but potassium and calcium levels were in the normal range. CFS group had a significant RH in comparison to SFS group (p<0.05). Conclusions: The serum sodium level was significantly lower in simple and complex seizures compared to the control group. Measurements of serum sodium levels and hyponatremia diagnosis have a key role on predicting the FS occurrence and recurrence. Therefore, physicians should be careful to administer the serums and inject the solutions for children with fever.