Epileptic encephalopathy with continuous spike-and-wave during sleep is a syndrome characterized by continuous spike-and-wave during sleep, seizures and progressive decline in cognitive, behavioral and psychiatric functioning.
NOTE 'Epileptic encephalopathy' denotes the concept that the epileptic activity itself might directly contribute additional cognitive and behavioral impairments over those expected from the underlying etiology alone, and that suppression of epileptic activity might minimize this additional impairment.
NOTE Childhood epilepsy with centrotemporal spikes, atypical childhood epilepsy with centrotemporal spikes, epileptic encephalopathy with continuous spike-and-wave during sleep and Landau Kleffner syndrome are syndromes that have in common certain EEG features, with variable severity of focal seizures and neurocognitive impairment. They may be considered as a spectrum, an individual child may show some features of more than one of these syndromes or transition from one to another over time.
This syndrome is characterized by onset of seizures between 2 and 12 years of age (peak 4-5 years), with epileptic encephalopathy with continuous spike-and-wave during sleep developing 1-2 years after seizure onset. Both sexes are affected. Antecedent and birth history are usually normal, or previous structural brain abnormalities may be present. Head size, neurological examination and developmental progress may be normal or reflect effects of an underlying structural brain abnormality.
A progressive decline in cognitive, behavioral and psychiatric functioning is a cardinal symptom of this syndrome. All cognitive domains are affected including language and communication, temporo-spatial orientation, attention and social interaction. The impairments are typically severe and although some improvement occurs in time, residual deficits remain after remission of seizures and EEG abnormality (which occurs from months to up to 7 years later).