Epileptic spasms with terror during sleep in CDKL5 encephalopathy.

Peculiar seizures with spasms starting in SWS are an early diagnostic clue in infants with CDKL5 encephalopathy. Sleep video-EEG polygraphy is an easy tool to disclose these early seizures and epileptic spasms in infants during the first months of life while polysomnography is unlikely to give a contribution at that early age. While conventional antiepileptic treatment and corticosteroids are poorly, transiently, or not efficient, therapeutic strategy used for sleep terror could help, although the mechanism of spasms generation in SWS needs to be elucidated.