Developmental and epileptic encephalopathy with spike-wave activation in sleep (D/EE-SWAS): Clinical and treatment insights from a cohort of 50 children

Background

Developmental and Epileptic Encephalopathy with Spike-Wave Activation in Sleep (D/EE-SWAS) is a rare and complex pediatric epilepsy syndrome characterized by cognitive and/or behavioral regression and nearly continuous spike-wave discharges during slow-wave sleep. D/EE-SWAS encompasses a spectrum of encephalopathies with heterogeneous etiologies and outcomes.

Objective

To assess etiology, clinical course, and treatment response in 50 children with D/EE-SWAS, with a focus on how underlying causes influence neuropsychological outcomes.

Methods

We retrospectively analyzed 50 children diagnosed with D/EE-SWAS at our center between 2005 and 2023. Patients were grouped into three etiological categories: self-limited focal epilepsies (SeLFE, n=19), structural brain abnormalities (n=18), and genetic causes (n=7). EEG features, cognitive and behavioral changes, and treatment responses were evaluated.

Results

Corticosteroids (80.9%), clobazam (55.8%), levetiracetam (54.1%), and sulthiame (52.9%) were the most effective treatments. SeLFE patients experienced shorter SWAS duration and better outcomes, while those with structural etiologies had more prolonged discharges and poorer responses. All patients showed cognitive and behavioral regression, with severity modulated by etiology.

Conclusion

D/EE-SWAS is a spectrum disorder with variable severity and prognosis depending on etiology. Early recognition and tailored treatment, especially in children with SeLFE, are essential to mitigate neurocognitive decline. This large single-center cohort provides new insights into the therapeutic challenges and outcome variability in D/EE-SWAS.