Neuro-glial degeneration in Status Epilepticus: Exploring the role of serum levels of Neurofilament light chains and S100B as prognostic biomarkers for short-term functional outcome.

Background: The last ILAE definition of Status Epilepticus (SE) highlights that the persistence of the epileptic activity per se could determine irreversible brain damages that could be responsible for long-term consequences. The measurement of neuro-glial injury biomarkers could help in the identification of those patients who will eventually develop short- and long-term consequences of SE. At present none of the already studied biomarkers has been validated to be used in everyday clinical practice. In this study, we explore the role of NfL and S100B as a prognostic biomarkers to identify patients who will develop short-term disability after an episode of SE.

Methods: This is a retrospective assessment of the serum levels of both NfL and S100B in a cohort of 87 adult patients with SE prospectively collected in our SE registry (Modena Status Epilepticus Registry - MoSER -) at Baggiovara Civil Hospital (Modena, Italy). All samples were acquired during SE within 72 hours of SE diagnosis. The comparison groups were: healthy controls (HC, n = 27) and patients with epilepsy (PWE, n = 30). Demographic, clinical, and therapeutical information and thirty-days follow-up information regarding disability development were acquired for every included patient and analyzed in relation to NfL and S100B values.

Results: Serum levels of NfL were significantly higher in SE compared to those of PWE (median 7.35 pg/ml, IQR 6.4, p < 0.001) and HC (median 6.57 pg/ml, IQR 9.1, p < 0.001); S100B serum levels were higher in SE (median 0.11 ug/L, IQR 0.18) compared to PWE (median 0.03 ug/L, IQR 0.03, p < 0.001) and HC (median 0.02 ug/L, IQR 0.008, p < 0.001). However, only NfL serum levels were found to be an independent predictor of 30 days functional outcome whereas S100B levels did not.

Conclusions: Our results suggest that NfL measurement in serum during SE could help predict the short-term functional outcome. This paper was presented at the 8th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in September 2022.