Immune response in blood before and after epileptic and psychogenic non-epileptic seizures

Inflammatory processes may provoke epileptic seizures and seizures may promote an immune reaction. Hence, the systemic immune reaction is a tempting diagnostic and prognostic marker in epilepsy. We explored the immune response before and after epileptic and psychogenic non -epileptic seizures (PNES). Serum samples collected from patients with videoEEG-verified tem-poral or frontal lobe epilepsy (TLE or FLE) or TLE + PNES showed increased interleukin-6 (IL-6) levels in between seizures (interictally), compared to controls. Patients with PNES had no in-crease in IL-6. The IL-6 levels increased transiently even further within hours after a seizure (postictally) in TLE but not in FLE patients. The postictal to interictal ratio of additionally five immune factors were also increased in TLE patients only. We conclude that immune factors have the potential to be future biomarkers for epileptic seizures and that the heterogeneity among different epileptic and non-epileptic seizures may be disclosed in peripheral blood sampling in-dependent of co-morbidities.

Automated summary

Inflammatory processes can trigger epileptic seizures, and seizures can promote an immune reaction. Therefore, the systemic immune reaction can be used as a diagnostic and prognostic marker in epilepsy. This study investigated the immune response before and after epileptic and psychogenic non-epileptic seizures (PNES). The results showed increased levels of interleukin-6 (IL-6) between seizures in patients with temporal or frontal lobe epilepsy (TLE or FLE) or TLE + PNES, compared to controls. The IL-6 levels further increased after a seizure (postictally) in TLE patients only. The study suggests that immune factors have the potential to be biomarkers for epileptic seizures and can help distinguish between different types of seizures.