CARBAMAZEPINE IN KCNQ2/3 AND SCN2A-RELATED EPILEPSY - A SCOPING REVIEW

Abstract

Purpose: To review the current evidence on the use of carbamazepine (CBZ) in treating KCNQ2/3 and SCN2A-related epilepsy with neonatal onset. Methods: We conducted a search on MEDLINE, Scopus, and Web of Science through November 2023. Studies reporting seizures in neonates with KCNQ2/3 and SCN2A variants that used carbamazepine to achieve seizure control were included. Results: Forty-eight neonates were identified in 13 studies that met the eligibility criteria. Epilepsy was associated with pathogenic variants in KCNQ2 in 39, KCNQ3 in 3, and SCN2A in 6. Positive family history was present in 17 cases (35.4%). All neonates had electroclinical seizures onset in the first week of life presenting with tonic or sequential seizures. Phenobarbital was used as first-line antiseizure medication (ASM) in 36 (75%) cases with no response. CBZ was used as first-line in 10 (20.8%) patients, with complete response in all. In 79,2% of patients, polytherapy was used, and CBZ was effective in seizure control in 30 (78.9%) patients. CBZ was initiated at a median of 12.5 days, with dosages ranging from 7 to 40 mg/kg/d. SCN2A patients needed higher doses and had a longer hospital stay. Neurodevelopmental outcomes were normal in all patients with KCNQ3, half of patients with KCNQ2 and only 17% of patients with SCN2A variants. Median follow-up time was 2.4 (1.4-6) years. Conclusion: Although evidence supporting the use of CBZ is based in case reposts and case series, it is described as very effective in seizures control associated with KCNQ2/3 and SCN2A-related epilepsy with neonatal onset.