EVOLUTION ATYPIQUE D’UNE EPILEPSIE PARTIELLE IDIOPATHIQUE DE L’ENFANT AU SERVICE DE NEUROLOGIE DU CHU FANN DE DAKAR - ATYPICAL EVOLUTION OF CHILDHOOD IDIOPATHIC PARTIAL EPILEPSY AT NEUROLOGICAL DEPARTMENT OF FANN HOSPITAL

RESUME  Introduction - Les pointes-ondes continues du sommeil constituent une encephalopathie epileptique dont certaines epilepsies partielles idiopathiques, y compris non rolandiques, peuvent faire le lit. Participants et methodes - Nous avons recueilli les donnees semiologiques cliniques et electrophysiologiques d’une patiente recue en consultation d’electroencephalographie, pour crises generalisees tonico-cloniques. Le trace de veille avait retrouve un foyer epileptique posterieur active en pointes-ondes continues au cours du sommeil. Resultats - Il s’agit d’une enfant de 10 ans qui a presente des hallucinations visuelles, des signes vegetatifs,   avec generalisation motrice secondaire puis cephalees postcritiques. Une seconde crise motrice a debut non precise a par la suite ete rapportee. L’examen clinique n’a pas retrouve d’anomalie neurologique ou autre. Les enregistrements electroencephalographiques ont montre des pointes-ondes diphasiques predominant en temporal et parietal, diffusant en occipital et en central, bloquees par l’ouverture des yeux. Lors de la sieste, apparaissaient des pointes-ondes continues du sommeil, maximales en temporal posterieur. L’imagerie par resonance magnetique cerebrale etait normale. Sous traitement, nous avons note un arret des crises et une diminution de l’activite des pointes-ondes continues du sommeil. Conclusion – L’activation du foyer de certaines epilepsies partielles idiopathiques en pointes-ondes continues du sommeil peut remettre en cause le pronostic plutot bon de ces epilepsies, du fait de la possible deterioration cognitive secondaire. Le role favorisant de certains traitements antiepileptiques n’est pas toujours verifie. En effet, chez notre patiente des POCS iatrogenes peuvent d’emblee etre ecartees, la patiente n’ayant pas beneficie de traitement antiepileptique auparavant. Il est important de faire un diagnostic precoce de ces POCS afin de preserver le pronostic cognitif de l’enfant.   SUMARY Introduction – Continuous spikes and waves during slow sleep are an epileptic encephalopathy occurring more frequently in the context of idiopathic partial epilepsy, not always benign childhood epilepsy with centrotemporal spikes. Participants and methods – We collected data about clinical and electrophysiological features of a patient we saw for generalized tonicoclonic seizures. Her electroencephalographic examinations revealed focal spikes and waves which were activated during sleep into continuous generalized spikes and waves. Results – A 10 years old young girl has had visual hallucinations with vegetative signs, then secondary motor generalization, and post-ictal headache. She reported a second seizure without details on the beginning. Clinical examination showed no neurological disorder or else. Electroencephalographic recordings revealed diphasic spikes and waves that were predominant in temporal and parietal areas, diffusing through occipital and central regions, and that were blocked during opening eyes. They turned into generalized continuous spikes and waves during slow waves sleep, predominating in posterior temporal area. Brain Magnetic Resonance Imaging was normal. The patient was free from seizure once she was treated and the activity of continuous spikes and waves during sleep decreased. Conclusion – The good prognosis of some childhood idiopathic partial epilepsies could be compromised through activation of electroencephalographic abnormalities into continuous spikes and waves during sleep, because of secondary cognitive disorders. Antiepileptic drugs are not always involved in this activation. That is the case of our patient who was free from any medication when the continuous spikes and waves during sleep were diagnosed. It is crucial to diagnose prematurely these continuous spike-waves in order to preserve intellectual functions. Key-words: continuous - spikes – waves – sleep - temporal - occipital