Circulating autoantibodies in unselected children with new-onset seizures

Abstract

Objective: The role of autoimmunity and autoantibodies is increasingly recognized in different forms of seizures and epilepsy. The prevalence of autoantibodies in new-onset epilepsy has recently been the focus of several cohorts in the adult and pediatric population, with positive titers in up to 10% of cases. Further work is needed to identify the subpopulation of patients with seizures in whom testing for neuronal autoantibodies could be performed as an integral part of the diagnostic work-up. The aim of this study was to determine the seropositivity rate in a non-selected group of children with new-onset seizures. Methods: Between September 2013 and April 2016, we prospectively recruited children aged 0 to 16 years with new-onset seizures, who presented at In- and Outpatient Pediatric Neurology Units from three Children's Hospitals in Switzerland. A large panel of circulating autoantibodies (Epilepsy Center, Bielefeld, CG. Bien) was analyzed in all patients in a 6 month-interval that followed their initial event. Results: A total number of 103 children were enrolled (mean age at presentation: 5 years, range 1 day – 15 years 9 months). 75 of them presented with generalized seizures. 6 had status epilepticus. At the time of onset, 55% of patients had fever. 27% needed hospitalization. Epilepsy was subsequently diagnosed in 18% of cases and AED treatment was initiated in 15%, 2 of which proved resistant to the first drug. Serum antibodies were found positive in only 2 patients: these were directed against the VGKC complex, with negative binding to the specific antigens LGI1 and CASPR2. Conclusion: This study demonstrates that serum antibodies are rarely found in an unselected population of children who present with a first seizure (1.9%). The clinical relevance in performing an extensive antineuronal antibody profile in a child with newly-onset seizures does therefore not appear to be justified.