“EPINEO” Monocentric Retrospective Study on Neonatal Seizures: Incidence, ILAE Seizure Type, Epileptic Syndrome, EEG and Etiology

Purpose: In the last decade important updates have occurred in the management of neonatal seizures (NS) that may have changed NS epidemiology. The International League Against Epilepsy (ILAE) has published a new classification for neonatal seizures. The aim of our study was to determine the current incidence of NS and the correlation between ILAE seizure type, epileptic syndrome, EEG and etiology. Materials and methods: This is a retrospective single-center cohort study on consecutive neonates with neurophysiological confirmation of NS from 2009 to 2022 performed in a tertiary neonatal center. Clinical information including medical history, neurological examination, EEG/aEEG, neuroimaging, laboratory tests were inserted on a specifically designed Redcap database. Seizure type and epileptic syndromes were classified according to the new ILAE classification andEEG/aEEG with INNESCO score. Results and conclusions: 145 neonates presented with NS: 101 term (69.7%) and 44 preterm (30.3). Incidence in the overall population at our center was 1.59/1000, in the inborn population 1.11/1000, increasing with earlier gestational age up to 17 times. In comparison with previous studies, we found a reduction in HIE-related NS and a higher contribution of genetic etiology to NS mediated by different mechanisms: functional epilepsy, metabolic epilepsy, structural epilepsy and acute provoked seizures (metabolic or vascular etiology) having a genetic etiology as primary cause triggering the cascade of events finally leading to seizures. Our study confirms the usefulness of the new ILAE classification for neonates to address etiology, confirming the association previously found between seizure type and etiology. A problematic issue is represented by the high risk of inter-operator variability regarding the use of the “sequential seizure” term. Specific types of sequential seizures with tonic-onset or tonic-clonic sequence patterns, often with alternating side onset within the same seizure or different seizures, are highly related to epileptic channelopathies.