P 125 Ring chromosome 20 Epilepsy syndrome in children Variable EEG- and electro-clinical pattern

摘要

Background Children with ring chromosome 20 epilepsy syndrome (rchr20es) typically show severe, drug-resistant focal epilepsies characterized by frontal semiology, high susceptibility for non-convulsive status epilepticus (NCSE) and epilepsy-associated cognitive and behavioral deteriorations. EEG has been reported to show frequent or continuous subclinical seizure patterns together with characteristic rhythmic theta waves (Caneveni et al. 1998). Here, we report on clinical and EEG data in four patients. Patients and methods Retrospective analysis of clinical and video-EEG-long-term-monitoring data of four patients (all female) with rchr20es. Age at onset of epilepsy ranged from 5 to 8 years, the number of antiepileptic drugs already used ranged from 6 to 10, and all four patients had suffered NCSE previously. Semiology: all four patients showed auras (epigastric: 2, fear: 2, visual: 1, somatosensory: 1) and seizures (hypermotor: 3, tonic: 3, dialeptic: 2, psychomotor: 2). Clinical epilepsy syndromes were frontal lobe epilepsies ( n = 3) and frontal/ temporal lobe epilepsy ( n = 1). EEG showed regional abnormalities in frontal ( n = 4), temporal ( n = 3) and parieto-occiptal ( n = 1) areas, with subclinical seizure patterns and/ or EEG-status elements (with serial spikes, polyspikes, sharp waves, or spike wave complexes; n = 3), rhythmic theta ( n = 2), 1–2 Hz slow sharp wave complexes ( n = 1), spike wave complexes/low amplitude fast activity +high amplitude delta burst ( n = 1), alpha/theta seizure activity ( n = 1). MRI was essentially normal in all patients, with minor abnormalities in frontal (2) or temporal areas (2). Conclusion Consistent with the literature, our patients showed severe drug-resistant epilepsies with an electro-clinical complex of a fronto-temporal epilepsy with frequent, long-lasting or continuous subclinical seizure patterns and/or NCSE. Rhythmic theta as a “characteristic” EEG pattern was, however, only observed in 2/4 of our patients. Therefore, a rchr20es should be suspected in such patients also in the absence of this EEG feature. This information will help in an early identification of rchr20es, which is especially important since, without this specific diagnosis, many affected patients are considered candidates for pre-surgical diagnostics or even epilepsy surgery. ]]>