The spectrum of neuropsychiatric abnormalities associated with electrical status epilepticus in sleep

Electrical status epilepticus in sleep (ESES) is an electrographic pattern consisting of an almost continuous presence of spike-wave discharges in slow wave sleep. ESES is frequently encountered in pediatric syndromes associated with epilepsy or cognitive and language dysfunction. It can be present in various evolutionary stages of a spectrum of diseases, the prototypes of which are the 'continuous spikes and waves during slow wave sleep' syndrome (CSWS), the Landau-Kleffner syndrome (LKS), as well as in patients initially presenting as benign childhood epilepsy with centrotemporal spikes (BECTS). The purpose of this article is to review the literature data on the semiology, electrographic findings, prognosis, therapeutic options, as well as the current theories on the pathophysiology of these disorders. The frequent overlap of CSWS, LKS, and BECTS urges an increased level of awareness for the occasional transition from benign conditions such as BECTS to more devastating syndromes such as LKS and CSWS. Identification of atypical signs and symptoms, such as high discharge rates, prolonged duration of ESES, neuropsychiatric and cognitive dysfunction, lack of responsiveness to medications, and pre-existing neurologic conditions is of paramount importance in order to initiate the appropriate diagnostic measures. Prolonged and if needed repetitive sleep electroencephalographs (EEGs) are warranted for proper diagnosis.