Abstracts

Rationale: Neonatal seizures are the most common neurological emergency in the newborn period. They can be associated with serious neurological sequlae including, epilepsy, cerebral palsy and intellectual deficits. A diagnosis of epilepsy can lead to a significant burden of disease. Challenging complex needs can be encountered that may be reduced with earlier identification of at risk infants, leading to prompt diagnosis and optimisation of delivery of care and seizure management.

Methods: A retrospective single-centre observational study of all infants admitted to the neonatal intensive care unit at Cork University Maternity Hospital, Ireland, between 2013-2017 with the following; 1) infants greater than or equal to 37 weeks gestation, 2) requiring EEG monitoring for at least 12 hours, 3) neurodevelopmental follow up. Infants who died during the neonatal period were excluded. Ethical approval was granted from the Clinical Research Ethics Committee of the Cork Teaching Hospitals.

Results: 94 term infants at risk of seizures monitored with EEG were included; the primary aetiology was HIE (59.6%) followed by genetic or metabolic encephalopathy and stroke. In total, 28 (28.4%) infants had electrographic seizures (ES); clinical characteristics are described in Table 1. 7/94 developed post-neonatal epilepsy (PNE), 5/28 (18%) in the electrographic seizure group and 2/66 (3%) in the no-electrographic seizure group. The aetiology in all seven infants with PNE was; epileptic encephalopathy (SCN2A mutation, n=2), Tuberous Sclerosis (n=1), moderate or severe HIE (n=2), inborn error of metabolism (IEM) (n=1) and an undiagnosed condition characterised by central hypoventilation (n=1). Despite the fact that HIE was the primary aetiology of seizures in the neonatal period, only 6% of infants with moderate and severe HIE developed PNE. In contrast, 44% of infants with genetic or metabolic encephalopathy developed PNE. Three infants developed epilepsy in the neonatal period (SCN2A and IEM), three within the first year and one at 44 months. Three infants with PNE died in childhood (< than 25 months) including all those who did not have electrographic seizures (moderate HIE and IEM).

Conclusions: Epilepsy is a serious neurological complication following neonatal encephalopathy. We have shown that post-neonatal epilepsy is higher in infants admitted to the NICU following electrographic confirmed seizures 18% vs 3%. Genetic or metabolic encephalopathy contributed the highest number of cases and all had electrographic seizures in the neonatal period. Only two infants developed PNE following HIE. Neonatal electrographic seizures present a clear risk for later PNE, particularly in infants with genetic and metabolic encephalopathy.

Funding: Please list any funding that was received in support of this abstract.: Carol Stephens is a clinical research fellow with INFANT Cork.