The Clinical and Neurophysiological Features of Epileptic Syndromes Associated with Benign Focal Epileptiform Discharges of Childhood

Abstract

Benign focal epileptiform discharge of childhood (BFEDC) is an age-dependent pattern determined in electroencephalograms (EEGs), which is associated with idiopathic benign focal epilepsy (BFE). Studies of BFE revealed symptomatic phenocopies in patients with cerebral struc- tural abnormalities in such conditions as infantile cerebral palsy and malformations. Some arguments against the «benign» nature of BFEDC are presented, since BFEDC may impair various cognitive functions and behavior (e.g., cause epileptic encephalophathies). Objective. To determine the clinical and neurophysiological features of epileptic syndromes associated with prolonged epileptiform activity during sleep in children and adolescents, as well as approaches to rational therapy. Patients and Methods . A total of 1862 children aged 2–18 admitted to the specialized Department of Psychoneurology of the Voronezh Regional Children Clinical Hospital No 1 in 2004–2007, who had epileptic seizures and non-epileptic neurological disorders, were exam- ined. The children underwent assessment of the neurological status, neuropsychological assessment, and video-EEG monitoring. The spike- wave index (SWI) was calculated and magnetic resonance imaging (MRI) of the brain was performed to register the epileptiform activity during sleep. Results and Discussion. It was demonstrated that when ISW of BFEDC patterns is >30%, evolution into epileptic encephalopathy was observed in 66% of patients (including epilepsy with electrical status epilepticus in sleep in 49% of patients and cognitive epileptiform disinte- gration in 17% of patients). The results prove the justification of prescribing antiepileptic drugs to patients with SWI ≥30% even if they have no epileptic seizures. Duo-therapy with valproate and ethosuximide or levetiracetam is most the effective therapy. Further prospective studies for children with BFEDC will give new insight into this area.