A study on epileptic negative myoclonus in atypical benign partial epilepsy of childhood.
OBJECTIVE
To investigate the clinical and neurophysiological characteristics, particularly therapeutic considerations, of epileptic negative myoclonus (ENM) in atypical benign partial epilepsy (ABPE) of childhood.


METHODS
From 1998 to 2006, 14/242 patients with benign children epilepsy with centrotemporal spikes (BECTS) were diagnosed as having ABPE with ENM. In all 14 patients, we performed video-EEG monitoring along with tests with the patient's arms outstretched; 6/14 patients were also simultaneously underwent surface electromyogram (EMG). ENM manifestations, electrophysiological features, and responses to antiepileptic drugs were analyzed.


RESULTS
In all cases, ENM developed after the onset of epilepsy and during antiepileptic drug therapy, and the appearance of ENM were corresponding to EEG findings of high-amplitude spikes followed by a slow wave in the contralateral motor areas with secondary generalization. This was further confirmed by time-locked silent EMG. During ENM occurrence or recurrence, habitual seizures and interictal discharges were exaggerated. In some patients, the changes in antiepileptic drug regimens in relation to ENM appearance included add-on therapy with carbamazepine, oxcarbazepine, and phenobarbital or withdrawal of valproate. ENM was controlled in most cases by administration of various combinations of valproate, clonazepam, and corticosteroids.


CONCLUSIONS
The incidence of ENM or ABPE in our center was approximately 5.79%. A combination of video-EEG monitoring with the patient's arms outstretched and EMG is essential to identify ENM. The aggravation of habitual seizures and interictal discharges indicate ENM. Some antiepileptic drugs, such as carbamazepine, oxcarbazepine, and phenobarbital, may be related to ENM occurrence during spontaneous aggravation of ABPE. Various combinations of valproate, benzodiazepines, and corticosteroids are relatively effective for treating ENM that occurs in ABPE.
Yang
Zhixian
Z
Department of Pediatrics, Peking University First Hospital, No. 1 Xi'anmen Street, Xicheng District, Beijing, PR China. zhixian.yang@163.com
Liu
Xiaoyan
X
Qin
Jiong
J
Zhang
Yuehua
Y
Bao
Xinhua
X
Chang
Xingzhi
X
Wang
Shuang
S
Wu
Ye
Y
Xiong
Hui
H
D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000927:Anticonvulsants / Q000627:therapeutic use; D001921:Brain / Q000187:drug effects / Q000503:physiopathology; D002220:Carbamazepine / Q000031:analogs & derivatives / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D002998:Clonazepam / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D004569:Electroencephalography; D004576:Electromyography; D004831:Epilepsies, Myoclonic / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology*; D004828:Epilepsies, Partial / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D000078330:Oxcarbazepine; D010634:Phenobarbital / Q000627:therapeutic use; D012640:Seizures / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology; D014635:Valproic Acid / Q000627:therapeutic use
D000305:Adrenal Cortex Hormones; D000927:Anticonvulsants; D002220:Carbamazepine; D002998:Clonazepam; D014635:Valproic Acid; D000078330:Oxcarbazepine; D010634:Phenobarbital