Cognitive impairment and behavioral disorders in Encephalopathy related to Status Epilepticus during slow Sleep: diagnostic assessment and outcome.

Encephalopathy related to Status Epilepticus during slow Sleep (ESES) is an age-dependent phenomenon, with usual spontaneous resolution during teenage years. However, cognitive outcome is often more disappointing, with permanent cognitive deficits in the large majority of children seen in later life. Presuming this to be an epileptic encephalopathy, current treatment practices are almost exclusively guided by the effect of the AEDs used on the degree of EEG abnormality in sleep. However, the major goal of therapy in ESES syndrome should in fact be to prevent or reduce associated cognitive and neurodevelopmental deficits. Whether or not the EEG pattern of ESES should be completely suppressed to improve cognition is unknown. Discussions on both diagnostic assessment and outcome of cognitive impairment and behavioral disorders should systematically take into account the complexity of the disorder; not only in terms of the evolution or fluctuations of the EEG patterns but also in relation to the underlying etiologies (at least lesional versus non-lesional) and age at diagnosis. We present a common basic assessment protocol, including the minimum technical requirements for polygraphic recording, and a treatment practice protocol that could both be applied in all centres dealing with this rare form of epilepsy. Such an approach would also allow a comprehensive collection of data prospectively, for a better understanding of the natural evolution of the disorder and an evidence-based evaluation of our practices.