Some genetic aspects of rolandic epilepsy: waking and sleep EEGs in siblings.

Epileptic activity was recorded electroencephalographically in at least one sibling in 22 (51.16%) of 43 patients with rolandic epilepsy and/or centrotemporal spikes. In 26 of 69 (37.68%) siblings, epileptic discharges were observed. These were recorded only in waking in 1 subject (1.5%), in waking and sleep in 13 (18.8%), and in sleep only in 12 (17.4%). The greatest number of epileptic discharges was noted in waking during hyperventilation (52.4%) and in sleep stage C (88%). Foci were recorded in only 4 (5.8%) of the 26 cases with epileptic discharges, and generalized spike-wave complexes were recorded in 22 (31.9%). In one sibling, the sharp-wave focus was located in the right centrotemporal area, in a second in the left occipital, and in a third in the left frontal region with spreading to the centrotemporal; in the fourth, two independent foci were observed in the left and right centrotemporal area. One epileptic discharge was observed every 74.9 s in waking and every 150.9 s in sleep. Epileptic activity was greatest in the group between 5 and 12 years of age (54.3%). The same activation rates were noted in siblings of patients with (47.2%) and without seizures (42.9%), and no differences were noted in siblings with (40%) or without (37.5%) seizures. Family history and sex of the siblings of patient did not play a role in the rate of activation. An autosomal dominant inheritance is assumed, but further investigations are necessary.