Epileptic encephalopathies occur when seizures, epileptiform EEG abnormalities, or both, result in impaired neurological and cognitive development and functioning. EEs represent about 40% of all epilepsies occurring in the first three years of life. West syndrome, Lennox-Gastatut syndrome, Dravet syndrome, myoclonic-astatic epilepsy and epilepsy with continuous spike and wave activity during sleep are the most frequently encountered forms. Some children, for example those suffering from Dravet syndrome, due to SCN1A have no detectable lesions, in which case most of the entire clinical picture is usually attributed to epilepsy, as suggested by the temporal relationship between the onset of seizures and evidence of developmental impairment. However a role for the ion channel disorder on cognitive functions cannot be excluded. When a brain lesion is present, however the concept of epileptic encephalopathy is not easily delineated, since an evaluation of the extent to which epilepsy related changes are likely to interfere with residual developmental potential could be arbitrary. There is no doubt, however, that the area of dysfunction that originates from a lesion may spread to anatomically intact areas and circuits that are distant from the primary lesion and drag them into a dysfunctional network. Vigorous early pharmacological or surgical treatment is often advocated on the assumption that epileptic activity would cause or worsen the encephalopathy per se. Some forms are responsive to specific treatments, but can be aggravated occasionally by classic anticonvulsants and especially polytherapy. However, for many of these conditions there are no established endpoints of treatment and drug adjustments are very empirically established. Complete seizure control should not be presented as a fundamental target to the parents. The main goal should be minimizing seizure frequency to an extent that seizures, per se, do not represent an impossible obstacle to social integration. This target can be reached by trying to find the right balance between side effects and seizures.
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