Developmental and/or Epileptic Encephalopathy with spike-wave activation in sleep (D/EE-SWAS)

Developmental and/or Epileptic Encephalopathy with spike-wave activation in sleep (D/EE-SWAS),refers to a spectrum of conditions that are characterized by the EEG feature of spike-wave activation in sleep, share similar clinical features and management implications. This syndrome now incorporates several syndromes previously named Landau-Kleffner syndrome, Epileptic Encephalopathy with Continuous Spike-Wave in Sleep and Atypical Benign Partial Epilepsy (pseudo-Lennox syndrome)and it is recommended that these terms no longer be used^[1].

• The EEG pattern previously required for this syndrome was known as continuous spike-wave in sleep (CSWS) and the clinical correlate previously known as electrical status epilepticus in
• sleep (ESES).
• Cognitive, behavioral, and motor regression occur at the same time or within weeks of EEG exhibiting SWAS, characterized by continuous, slow (1.5-2Hz) spike-waves in slow sleep, typically occupying >50% of slow sleep.
• The diagnosis of D/EE-SWAS requires that the child show temporally related cognitive, behavioral or motor regression with the EEG pattern
• EE-SWAS occurs in a child with normal development, whereas D/EE-SWAS occurs in one with preexisting developmental delay or just language delay.
• Children may present with an auditory agnosia where they do not recognize common sounds, such as the doorbell or telephone ringing. They show loss of understanding and have an acquired aphasia.
• Seizures do not occur in all children. When present they may range from easily controlled focal motor seizures to drug-resistant seizures of multiple types
• Specific focal epilepsy syndromes, such as SeLECTs and SeLEAS, or other structural focal epilepsies may evolve to D/EE-SWAS, either transiently or for a prolonged period.