Epilepsia de ausencia de inicio precoz: a propósito de un caso / Premature start absence epilepsy: by the way of a case

Se presenta un caso de epilepsia de ausencia de inicio antes de los 2 años de edad, que requirió múltiples drogas antiepilépticas. Se revisa la bibliografía sobre el tema y se profundiza en las actuales variaciones de los criterios diagnósticos en relación con los síndromes de ausencia epiléptica y las variantes de presentación que pueden ser causa de errores diagnósticos y terapéuticos. Se confirma el importante papel de la monitorización electroencefalográfica y videoelectroencefalográfica como herramienta diagnóstica en las epilepsias de presentación poco común en la infancia. Se revisan los factores etiológicos polimórficos actuales, el papel de los canales iónicos y el uso de las drogas antiepilépticas en la ausencia infantil.

A case of absence epilepsy that began before the second year of life and required many antiepileptic drugs was presented. A literature review was made on this topic, delving into the present variations of diagnostic criteria related to epileptic absence syndromes and their various presentations that may derive from diagnostic and therapeutical mistakes. The important role of electroencephalographic and videoelectroencephalographic monitoring as a diagnosing tool in rare epilepsies in childhood was confirmed. The present etiological polymorphic factors, the role of ion channels and the use of antiepileptic drugs in infantile absence epilepsy were reviewed.

Interaction of flunarizine with sodium valproate or ethosuximide in gamahydroxybutyrate induced absence seizures in rats.

Sodium valproate(VPA), ethosuximide(ESM), 200 mg/kg ip and flunarizine (FLU) 5 or 10 mg/kg ip were first administered independently to rats in order to study their effects on behavioural and EEG aspects of spike and wave discharges (SWDs) induced by y- hydroxybutyrate (GHB,100 mg/kg ip). GHB treated rats show behavioural changes and concomitant repetitive EEG episodes of 7 to 9 Hz SWDs, mimicking human absence seizures (AS), and can be used as a pharmacological model. The number and duration of SWDs were calculated for 1 hr from the EEG and were parameters for drug evaluation. VPA and ESM at 200 mg/kg, significantly reduced SWD number and duration/hr, while FLU showed significant reduction only at 10 but not at 5 mg/kg. Combination of FLU, 10 mg/kg with either VPA or ESM showed significant reduction of SWD number and duration, suggesting an additive effect of the anti-absence agents with the calcium channel blocker, FLU, on experimental absence seizures in rats.

Comparative profiles of sodium valproate and ethosuximide on electro-behavioural correlates in gamma-hydroxybutyrate and pentylenetetrazol induced absence seizures in rats.

Sodium valproate (VPA) and ethosuximide (ESM) were compared on behavioural and EEG changes in gamma-hydroxybutyrate (GHB) and pentylenetetrazole (PTZ) rat models of Absence Seizures (AS). Both GHB, 100 mg/kg i.p. and PTZ, 20 mg/kg i.p., produced repetitive episodes of staring and immobility with concomitant 6 to 9 Hz spike and wave discharges (SWDs) in the EEG. The parameters used for drug evaluation were the number and duration of SWDs/hour. Though the number of SWDs/hour produced by GHB and PTZ were not significantly different, the duration of SWDs was significantly longer in GHB treated rats (P < 0.001) VPA and ESM, at 200 mg/kg i.p., reduced SWD number and duration in GHB pretreated rats, whereas ESM, 50 mg/kg i.p., was four times more effective than VPA, 200 mg/kg i.p., in the PTZ model. Phenytoin (PHY) 20 and Carbamazepine (CBZ) 10 mg/kg i.p., worsened AS, a feature which has also been reported clinically. Both rat models of experimental AS can be used to defect potential anti-absence activity in new chemical entities.

Additive anticonvulsant effect of flunarizine and sodium valproate on electroshock and chemoshock induced seizures in mice.

The efficacy of Flunarizine (FLU), a calcium channel blocker, in combination with conventional antiepileptic drugs, phenytoin (PHT), carbamazepine (CBZ), sodium valproate (VPA), and ethosuximide (ESM), at ED50 doses, were examined for protective effects against maximal electroshock seizures (MES) and pentylenetetrazol (PTZ) induced seizures in mice. In both models, only VPA and FLU showed significantly enhanced protection, which was additive ie. 100% protection. In the MES test, though FLU combined with PHT did show a slightly enhanced protection (66.6%), with CBZ there was no enhancement as compared to either drug alone. In the PTZ test, FLU with ESM showed 83% protection this however was not statistically significant. The findings of this study in mice suggest that FLU would be a suitable candidate for add-on therapy with VPA for clinical epilepsy.

Epilepsia fotosensible: aspectos clínicos y electroencefalográficos / Photosensitive epilepsy: clinics and electroencephalografic aspect

El objetivo de este estudio es la evaluación clínica y electroencefalográfica de las epilepsias fotosensibles. Se analizaron 14 pacientes (p) con epilepsia fotosensible EF, 9 de ellos con EF pura y 5 p con crisis autoinducidas. 10 fueron varones y 4 mujeres. Edad media de comienzo de las crisis autoinducidas 5 ñ 2 años (2-8) y de la epilepsia fotosensible pura, 9 ñ 3 años (4-13). El tiempo de seguimiento fué de 11 ñ 10 años (1-30). A todos se les realizó un electroencefalograma (EEG) con estimulación luminosa intermitente (ELI) en 1994. Las crisis fueron inducidas por el sol en 3 p, televisión (TV) en 4 p, sol y TV en 4 p, y video-juegos en 3 pacientes; 12 epilepsias fueron idiopáticas y 2 sintomáticas. Antecedentes familiares de epilepsia se determinaron en un 43 por ciento. Luego del tratamiento, 5 p normalizaron su EEG (35,71 por ciento) pero 9 p (64,29 por ciento) conservan la respuesta anormal a la ELI y de éstos últimos 7 continúan con crisis. Todos los p con crisis por video-juegos una vez comenzado el tratamiento normalizaron el EEG y no presentaron más crisis. Conclusión: Entre las epilepsias fotosensibles puras aquellas inducidas por video-juegos parecen ser las más benignas. La persistencia del EEG con respuesta fotoconvulsiva predice el pobre control de las crisis fotosensibles