Neonatal Seizures in Tuberous Sclerosis Complex: A Case Series.

Epilepsy affects up to 90% of patients with tuberous sclerosis complex (TSC); earlier seizure onset is associated with worse neurocognitive outcomes. The incidence of neonatal seizures in TSC is unknown, although in a recent multicenter trial 23% of infants with TSC were excluded prior to randomization because of pre-existing seizures prior to age 4 months, suggesting that neonatal or early infantile seizures may be a common occurrence. We aimed to determine the rate of neonatal seizures in our cohort of TSC patients. We performed a single-center medical records review of patients with TSC who were seen between 2020 and 2025 to identify patients with neonatal seizure onset. Of six patients with data from the neonatal period, four (67%) had neonatal seizures. Two had confirmed electrographic seizures in the first week of life, and another two had clinical seizure onset during the neonatal period. All patients with neonatal seizures had TSC2 and developed drug-resistant epilepsy, and two of four developed infantile spasms despite intensive early medical management, including vigabatrin. The two patients without neonatal seizures had TSC1 and mosaic TSC2, respectively. They have not developed epilepsy and have had milder neurodevelopmental impairment.In conclusion, data from our center suggest that neonatal seizures may be common in TSC, especially in high-risk infants with TSC2 with highly epileptogenic lesions. With recent preliminary data about safety and efficacy of mTOR inhibitor treatment in infants with TSC, early EEG monitoring should be considered.