What is the interest of the electroencephalogram in the syndromic diagnosis?

INTRODUCTION: The identification of the epileptic syndrome is a challenge particularly in childhood epilepsies. In fact, the diagnosis may need several years to be fulfilled. OBSERVATION: Our patient presented at the age of 3 years 6 months atypical absence. His electroencephalogram (EEG) showed generalized spikes and waves andpolyspikes and waves. At age 6, he has developed other types of seizures: slow fall of the head, shoulders jerks,slow fall to the side and loss of consciousness. All these phenomena were organized in a fortuitous and variable association from one period to another over 2 years. Meanwhile, the child developed cognitive impairment. EEG showed fast rhythms in sleep and waking. It was only at the age of 8years, whenthe child developedtonic seizures,that we made the diagnosis of Lennox-Gastaut syndrome. CONCLUSION: In the absence of Specific Markers, syndromic diagnosis in epilepsy remains Electro- clinical.