Dravet Syndrome with Neurological Progression and Systemic Findings: A Case Report

Abstract

Objective: This case report aims to evaluate the clinical course, EEG, imaging findings, developmental status, and treatment of a patient with Dravet Syndrome associated with an SCN1A mutation from a multidisciplinary perspective. Case Report: A 36-week premature female infant experienced a febrile hemiclonic seizure, followed by refractory epileptic attacks including status epilepticus, tonic-clonic, absence, and myoclonic seizures. Initially normal or mild, the EEG findings worsened over time, evolving from Lennox-Gastaut-like patterns to modified hypsarrhythmias reflecting epileptic encephalopathy. Genetic analysis confirmed an asymptomatic (heterozygous) SCN1A mutation in the father. Developmental assessments revealed a mild initial delay but later progressed to a marked, widespread impairment in all domains. Despite multiple combinations of antiepileptic drugs and a ketogenic diet, complete seizure control was not achieved. Conclusion: This case highlights the multifaceted clinical deterioration of Dravet syndrome, characterized by treatment-resistant seizures, marked neurophysiological progression, and systemic organ involvement. The findings highlight the critical importance of early genetic diagnosis and a comprehensive, multidisciplinary approach in the management of this complex and progressive syndrome to optimize long-term outcomes.

Keywords

• Case Report
• Dravet Syndrome
• Mutation
• Pediatric Epileps
• SCN1A

Supporting Institution

None to declare.

Ethical Statement

Ethical approval was obtained from the Istanbul Bilgi University Ethics Committee (Decision date: 22 December 2025; Project/Protocol No: 2025-40162-267; Document No: 01.01.2026-56135). This case report was prepared retrospectively using de-identified clinical data obtained during routine care. All identifiable information has been removed, and the report does not contain any images that could identify the patient.

References

1. Dravet C. Dravet syndrome history. Dev Med Child Neurol. 2011;53(Suppl 2):S1-S6.
2. He Z, Li Y, Zhao X, Li B. Dravet syndrome: advances in etiology, clinical presentation, and treatment. Epilepsy Res. 2022;188:107041. doi:10.1016/j.eplepsyres.2022.107041.
3. Li W, Schneider AL, Scheffer IE. Defining Dravet syndrome: an essential pre-requisite for precision medicine trials. Epilepsia. 2021;62(9):2205-2217. doi:10.1111/epi.17015.
4. Strzelczyk A, Kalski M, Bast T, Wiemer-Kruel A, Bettendorf U, Kay L, et al. Burden-of-illness and cost-driving factors in Dravet syndrome patients and carers: a prospective, multicenter study from Germany. Eur J Paediatr Neurol. 2019;23(3):392-403. doi:10.1016/j.ejpn.2019.02.014.
5. Han Z, Chen C, Christiansen A, Ji S, Lin Q, Anumonwo C, et al. Antisense oligonucleotides increase Scn1a expression and reduce seizures and SUDEP incidence in a mouse model of Dravet syndrome. Sci Transl Med. 2020;12(558):eaaz6100. doi:10.1126/scitranslmed.aaz6100.
6. Cooper MS, McIntosh A, Crompton DE, McMahon JM, Schneider A, Farrell K, et al. Mortality in Dravet syndrome. Epilepsy Res. 2016;128:43-47. doi:10.1016/j.eplepsyres.2016.10.006.
7. Shao W, Liu L, Gu J, Yang Y, Wu Y, Zhang Z, et al. Spotlight on mechanism of sudden unexpected death in epilepsy in Dravet syndrome. Transl Psychiatry. 2025;15(1):84. doi:10.1038/s41398-025-03304-8.
8. Kearney J. Sudden unexpected death in Dravet syndrome: SUDEP in Dravet mouse model. Epilepsy Curr. 2013;13(6):264-265.

9. Cetica V, Chiari S, Mei D, Parrini E, Grisotto L, Marini C, et al. Clinical and genetic factors predicting Dravet syndrome in infants with SCN1A mutations. Neurology. 2017;88(11):1037-1044. doi:10.1212/WNL.0000000000003716.
10. Heron SE, Scheffer IE, Iona X, Zuberi SM, Birch R, McMahon JM, et al. De novo SCN1A mutations in Dravet syndrome and related epileptic encephalopathies are largely of paternal origin. J Med Genet. 2010;47(2):137-141.
11. Ceska K, Danhofer P, Horak O, Spanelova K, Kolar S, Oslejskova H, et al. Phenotypic spectrum of the SCN1A mutation (from febrile seizures to Dravet syndrome). Bratisl Lek Listy. 2022;123(7):483-486.
12. Fan HC, Yang MT, Lin LC, Chiang KL, Chen CM. Clinical and genetic features of Dravet syndrome: a prime example of the role of precision medicine in genetic epilepsy. Int J Mol Sci. 2023;25(1):31. doi:10.3390/ijms25010031.
13. Zuberi SM, Wirrell E, Yozawitz E, Wilmshurst JM, Specchio N, Riney K, et al. ILAE classification and definition of epilepsy syndromes with onset in neonates and infants: Position statement by the ILAE Task Force on Nosology and Definitions. Epilepsia. 2022;63(6):1349-1397. doi:10.1111/epi.17239.
14. Minato E, Myers KA. Age-related evolution of EEG in Dravet syndrome: Meta-analysis of 155 patients. Seizure. 2021;91:108-111. doi:10.1016/j.seizure.2021.06.007.
15. Kapoor D, Anand A, Sharma S, Mukherjee SB, Marini C, Mei D, et al. Dravet syndrome: a case series. Indian J Pediatr. 2021;88:82. doi:10.1007/s12098-020-03383-z.
16. Fine AL. ENVISIONing a critical period to preserve development: communication delays in SCN1A+ Dravet syndrome. Epilepsy Curr. 2024;24(5):342-344. doi:10.1177/15357597241280687.
17. Wirrell EC, Hood V, Knupp KG, Meskis MA, Nabbout R, Scheffer IE, et al. International consensus on diagnosis and management of Dravet syndrome. Epilepsia. 2022;63(7):1761-1777. doi:10.1111/epi.17274.
18. Heger K, Lund C, Larsen Burns M, Bjørnvold M, Sætre E, Johannessen SI, et al. A retrospective review of changes and challenges in the use of antiseizure medicines in Dravet syndrome in Norway. Epilepsia Open. 2020;5(3):432-441. doi:10.1002/epi4.12413.
19. Scheffer IE, Halford JJ, Miller I, Nabbout R, Sanchez-Carpintero R, Shiloh-Malawsky Y, et al. Add-on cannabidiol in patients with Dravet syndrome: results of a long-term open-label extension trial. Epilepsia. 2021;62(10):2505-2517. doi:10.1111/epi.17036.
20. Sullivan J, Lagae L, Cross JH, Devinsky O, Guerrini R, Knupp KG, et al. Fenfluramine in the treatment of Dravet syndrome: results of a third randomized, placebo-controlled clinical trial. Epilepsia. 2023;64(10):2653-2666. doi:10.1111/epi.17737.
21. Chiron C, Marchand MC, Tran A, Rey E, d’Athis P, Vincent J, et al. Stiripentol in severe myoclonic epilepsy in infancy: a randomised placebo-controlled syndrome-dedicated trial. Lancet. 2000;356(9242):1638-1642.
22. Li Y, Dai S, Deng Q, Liu Z. The impact and adherence of ketogenic dietary therapies for Dravet syndrome: a systematic review and meta-analysis. Seizure. 2025;130:16-24. doi:10.1016/j.seizure.2025.05.001.
23. Yu M, Li H, Sun D, Li D, Zhong J, Gu Q, et al. The ketogenic diet for Dravet syndrome: a multicenter retrospective study. Nutrition. 2023;110:111976.
24. Villas N, Meskis MA, Goodliffe S. Dravet syndrome: characteristics, comorbidities, and caregiver concerns. Epilepsy Behav. 2017;74:81-86.
25. Minderhoud CA, Postma A, Jansen FE, Verhoeven JS, Schrijver JJ, Goudswaard J, et al. Gastrointestinal and eating problems in SCN1A-related seizure disorders. Epilepsy Behav. 2023;146:109361. doi:10.1016/j.yebeh.2023.109361.