A study on epileptic negative myoclonus in atypical benign partial epilepsy of childhood

The Prevalence and Risk Factors of Electrical Status Epilepticus During Slow-Wave Sleep in Self-Limited Epilepsy With Centrotemporal Spikes

Objective. To investigate the prevalence and risk factors for electrical status epilepticus during slow-wave sleep (ESES) in patients with self-limited epilepsy with centrotemporal spikes (SeLECTS). Methods. The clinical and follow-up data of children with SeLECTS were collected between 2017 and 2021. Patients were divided into typical ESES, atypical ESES, and non-ESES groups according to spike-wave indices (SWI). Clinical and electroencephalography characteristics were retrospectively analyzed. Logistic regression was used to identify risk factors for ESES. Results. A total of 95 patients with SeLECTS were enrolled. Seven patients (7.4%) developed typical ESES, 30 (31.6%) developed atypical ESES, 25 (26.3%) developed ESES at the first visit, and 12 (12.6%) developed ESES during treatment and follow-up. Multivariate logistic regression analysis showed that the risk factors for SeLECTS combined with ESES were Rolandic double or multiple spikes (OR = 8.626, 95% CI: 2.644-28.147, P < .001) and Rolandic slow waves (OR = 53.550, 95% CI: 6.339-452.368, P < .001). There were no significant differences in seizure characteristics, electroencephalogram (EEG) findings, or cognitive impairment between the atypical and typical ESES groups. Conclusion. More than one-third of the SeLECTS patients combined with ESES. Both atypical and typical ESES scores can affect cognitive function. On electroencephalography, interictal Rolandic double/multiple spikes and slow-wave abnormalities may indicate SeLECTS with ESES.

Genetic Epilepsy Syndromes

PURPOSE OF REVIEW

This article reviews the clinical features, typical EEG findings, treatment, prognosis, and underlying molecular etiologies of the more common genetic epilepsy syndromes. Genetic generalized epilepsy, self-limited focal epilepsy of childhood, self-limited neonatal and infantile epilepsy, select developmental and epileptic encephalopathies, progressive myoclonus epilepsies, sleep-related hypermotor epilepsy, photosensitive occipital lobe epilepsy, and focal epilepsy with auditory features are discussed. Also reviewed are two familial epilepsy syndromes: genetic epilepsy with febrile seizures plus and familial focal epilepsy with variable foci.

RECENT FINDINGS

Recent years have seen considerable advances in our understanding of the genetic factors underlying genetic epilepsy syndromes. New therapies are emerging for some of these conditions; in some cases, these precision medicine approaches may dramatically improve the prognosis.

SUMMARY

Many recognizable genetic epilepsy syndromes exist, the identification of which is a crucial skill for neurologists, particularly those who work with children. Proper diagnosis of the electroclinical syndrome allows for appropriate treatment choices and counseling regarding prognosis and possible comorbidities.

Epileptic negative myoclonus restricted to lower limbs in benign childhood focal epilepsy with vertex spikes

BACKGROUND AND PURPOSE

The aim was to determine the electroclinical findings in benign childhood focal epilepsy with vertex spikes (BEVS) with epileptic negative myoclonus (ENM) restricted to the lower limbs.

METHODS

The electroencephalogram database of Peking University First Hospital and medical records of patients with BEVS and ENM restricted to the lower limbs were reviewed.

RESULTS

Twenty-seven patients with BEVS had ENM restricted to the lower limbs. Twelve started as ENM restricted to the lower limbs. The age at seizure onset ranged from 1.5 to 4.8 years. During the course, half of the 12 patients developed focal sensorimotor seizures and then were diagnosed as benign childhood epilepsy with centrotemporal spikes (BECTS), with BEVS (four cases) and without BEVS (two cases). Five of them had electrical status epilepticus during sleep (ESES) and met the diagnostic criteria of atypical benign partial epilepsy (ABPE). Fifteen of the 27 patients had ENM restricted to the lower limbs during the course. The age at seizure onset ranged from 1.3 to 9.8 years. All had ESES and were diagnosed as ABPE, 11 as ABPE with BEVS and four as ABPE evolving into BEVS.

CONCLUSIONS

Benign childhood focal epilepsy with vertex spikes (BEVS) might represent a specific epileptic syndrome of the continuum of benign childhood focal epilepsy. ENM restricted to the lower limbs was a special phenomenon in BEVS. BEVS could overlap with BECTS or evolve into BECTS and further into ABPE and vice versa. Ignorance of vertex spikes with associated ENM restricted to the lower limbs might lead to a misunderstanding of BEVS, a specific type of benign childhood focal epilepsy.

Epileptic Negative Myoclonus as the First and Only Symptom in a Challenging Diagnosis of Benign Epilepsy With Centrotemporal Spikes

OBJECTIVE

To investigate the clinical and neurophysiological characteristics of epileptic negative myoclonus as the first and only ictal symptom of benign epilepsy with centrotemporal spikes.

METHODS

Electrophysiological evaluations included polygraphic recordings with simultaneous video electroencephalogram monitoring and tests performed with patient's upper limb outstretched in standing posture. Epileptic negative myoclonus manifestations, electrophysiological features, and responses to antiepileptic drugs were analyzed.

RESULTS

The authors report 2 patients with benign epilepsy with centrotemporal spikes, who had epileptic negative myoclonus as the first and only seizure type. Video electroencephalogram monitoring results showed that their negative myoclonus seizures were emanating from the contralateral central and the parietal regions. Epileptic negative myoclonus was controlled by administration of valproate and levetiracetam.

CONCLUSION

Epileptic negative myoclonus can be the first and only seizure type of benign epilepsy with centrotemporal spikes, and long-term follow-up monitoring should be the care for the recurrence and/or presence of other types of seizures.

Epileptic negative myoclonus as the presenting seizure type in rolandic epilepsy

Epileptic negative myoclonus is an uncommon seizure type characterized by a sudden, brief loss of muscle tone that may lead to falling. It has been associated largely with benign childhood epilepsy with centrotemporal spikes (rolandic epilepsy), although it may also be a feature of other epileptic syndromes. In patients with rolandic epilepsy, epileptic negative myoclonus usually appears during the course of the disease, well after a diagnosis of the epilepsy has been established. Described here are five patients with rolandic epilepsy in which the presenting seizure was falls due to epileptic negative myoclonus. Because developmental delay or neurocognitive problems were present in three of the children, it is possible that epileptic negative myoclonus may be misinterpreted as clumsiness-related falls in some children who actually have undiagnosed rolandic epilepsy.

Epileptic negative myoclonus: SPECT, PET, and video/EEG studies and the dramatic effects of levetiracetam

An 18-year-old woman presented with epileptic negative myoclonus (ENM) as her major seizure pattern for 4years. Her seizures were characterized by intermittent postural lapse of the right limbs for a period of hours to 2 days. Ictal electroencephalography (EEG)-electromyography showed a silent period that was time-locked to generalized spike-wave discharges. Video/EEG monitoring demonstrated marked improvement of ENM after oral administration of levetiracetam. Cranial magnetic resonance imaging was normal, but 2-deoxy-2-[(18)F]fluoro-d-glucose positron emission tomography during frequent ENM showed hypometabolism in the left frontoparietal cortex. Technetium-99m-ethyl cysteinate dimer single-photon emission computed tomography revealed hyperperfusion over the left parietal cortex and putamen. Here, we document the short-term effects of levetiracetam in this subject with nearly isolated ENM and the neuroimaging results during ENM. Long-term follow-up is in progress to evaluate the clinical evolution and long-term effects of levetiracetam on ENM.