Early myoclonic encephalopathy. Delimitation of the syndrome in view of genetic counseling

: Early myoclonic encephalopathy is a rare neurologic disease of unknown etiology whose course is always quickly unfavorable. Clinical features include lack of mental development and myoclonic jerks which appear during the neonatal period. There are no biological abnormalities but EEG shows a pattern of suppression-burst. In the spectrum of neonatal epileptic encephalopathic syndromes, it is important to distinguish this syndrome from non-ketotic hyperglycinemia and Ohtahara' syndrome. Two new familial cases authors to emphasize on the difficulty of nosological delineation of these syndromes. However it is necessary to delimit this disease for a genetic purpose.