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Objectives Neurological causes are common diagnoses for apparent life-threatening events in infants. The objective of this study was to evaluate the relevancy of electroencephalography performed after an apparent life-threatening event. Material and methods A retrospective study was conducted in a children's hospital over a 1-year period. The charts of infants under 2 years of age who were admitted following an apparent life-threatening event were reviewed. Clinical and biological data were collected and electroencephalograms - divided into normal and abnormal - were reviewed. To evaluate the follow-up state of the patients, parents were invited to complete an evaluation form an average 13 months after the event. The yield for electroencephalography was established according to the ratio of positive results contributing to the diagnosis of the cause of the apparent life-threatening event. Results A total of 47 patients met the inclusion criteria. Fifteen had had an EEG, 32 had not. The rate of abnormal neurological signs described by parents during the apparent life-threatening event was higher in the EEG group compared to the group without EEG (53% vs. 22%, P=0.05). In the follow-up, 35% of the children presented a second event, which was described as being similar or less impressive and occurred in the 1st month after the event (91%). Of the eight abnormal electroencephalograms, six had no specific abnormalities and two contributed to the diagnosis of epileptic seizure. Therefore, the diagnostic yield of electroencephalography in this study was 13% (2/8). Conclusions The yield of electroencephalography performed after an apparent life-threatening event is low. Neurological history and repeated physical examinations still remain the major diagnostic tools before resorting to electroencephalography.

Resume Cette revue a pour but d'exposer la classification nosologique des « convulsions » neonatales, de preciser leurs causes, leur pronostic et de proposer une conduite diagnostique et therapeutique. Les crises peuvent etre de nature epileptique ou non, etre occasionnelles ou entrer dans le cadre d'une maladie epileptique ou metabolique. L'electroencephalogramme (EEG) a un role essentiel. En effet, il permet de confirmer le caractere epileptique des crises, d'en evaluer le pronostic, de guider le traitement et parfois de contribuer au diagnostic. Le bilan doit etre complete par l'imagerie (IRM) et par d'autres examens en fonction de l'orientation diagnostique. Il est essentiel d'aller le plus loin possible dans la recherche etiologique et de ne pas attribuer a une cause occasionnelle (en particulier a une encephalopathie anoxo-ischemique dont les criteres diagnostiques sont stricts) des convulsions d'autre origine, genetique ou en rapport avec une pathologie maternelle. Le traitement comprend plusieurs volets : le traitement de la cause des crises, le cas echeant celui des pathologies associees, le soutien des grandes fonctions vitales, et enfin le traitement antiepileptique. Il repose, pour les crises occasionnelles, en premier lieu, sur le phenobarbital, puis sur l'utilisation d'autres produits dont l'effet est immediat, et sur le pronostic a long terme demande a etre evalue de facon tres rigoureuse. A cote des crises occasionnelles, les syndromes epileptiques a debut neonatal et des maladies metaboliques sont une cause rare des crises neonatales. Les reconnaitre permet d'etablir le pronostic, de debuter rapidement un traitement approprie et specifique en fonction du syndrome epileptique et, quelques fois, de proposer un diagnostic antenatal. Les erreurs innees du metabolisme sont importantes a reconnaitre et necessitent une prise en charge urgente et specialisee. Un pronostic globalement mauvais, des convulsions neonatales dependent essentiellement de la cause des crises et, probablement aussi a un moindre degre, de leur persistance.

Metabolic disorders constitute an important cause of neurologic disease, including neonatal epilepsy. Epilepsy rarely dominates the clinical presentation, which is more frequently associated with other neurologic symptoms, such as hypotonia and/or vigilance disturbances. In most cases, epilepsy secondary to inherited metabolic disorders presents with polymorphic clinical and electrographic features that are difficult to classify into precise epileptic syndromes. However, specific types of seizures, such as myoclonic seizures or distinctive electroencephalographic patterns, such as suppression burst patterns, epileptic syndrome or early myoclonic encephalopathy, may suggest a specific metabolic disease. The aim of this article is to help clinicians in reviewing potential metabolic diagnoses and approaching metabolic evaluations.

Epilepsy is among the most frequent finding in many chromosome aberrations. While most chromosome aberrations can be associated with different seizure types, there are few aberrations which feature specific seizures and EEG patterns. Among the 400 different chromosomal imbalances described with seizures and EEG abnormalities, eight have a high association with epilepsy. These comprise: the monosomy 1p36, Wolf-Hirschhorn syndrome (4p-), Angelman syndrome, Miller-Dieker del 17p13.3, the inversion duplication 15 syndrome, ring 20 and ring 14 syndromes, Down's syndrome. These chromosomal regions where aberrations have an evident association with epilepsy may be useful targets for gene hunters. On the other hand, a better characterisation of epileptic syndrome in these disorders may lead to a better and specific treatment.