EPILESSIA MIOCLONICA INTERMEDIARIA CRIPTOGENETICA DEL BAMBINO: EVOLUZIONE E PROGNOSI

The authors describe the clinical features and course of cryptogenic intermediary myoclonic epilepsy of childhood (EMI), observed in 11 patients with an average follow-up of 6 years (range 2-11 years). All patients underwent polygraphic recordings (electroencephalogram, electrocardiogram, pneumogram, electromyogram) with the help of audiovisual aids for simultaneous display of seizures and tracings during wakefulness and sleep. EMI presents the following features: unknown origin; massive myoclonic seizures as the only or main attacks; onset usually around 3 years; slight mental retardation in over 50% of cases; seizures ceased in a third of cases, diminished in a third and remained unchanged in a third. In comparison with benign myoclonic epilepsy, severe myoclonic epilepsy and the myoclonic variant of Lennox-Gastaut syndrome, EMI has a relatively benign (intermediate) course. Identification of EMI further confirms the fact that among the myoclonic epilepsies, alongside well-defined forms in which evolution of the disease can be predicted fairly accurately, there exists a whole series of observations with a more uncertain prognosis and course defined as 'intermediate' forms. The separation of syndromes with a benign, malignant and intermediate course is useful for the purposes of correct epileptic therapy and above all, to give parents an accurate early prognosis of the consequences that epilepsy may have for their child.