Focal epilepsy due to de novo SCN1A mutation.

OBJECTIVE: Our aim was to identify patients with SCN1A-related epilepsy with a phenotype of pure focal epilepsy. METHODS: We conducted a retrospective study and a systematic review in Pubmed to identify patients with focal epilepsy associated with SCN1A pathogenic variants. RESULTS: We found three patients among 1,191 in our rare epilepsy database in 2017. The literature search from January 2000 to September 2019 led to identification of four patients with limited data. Our three patients had a common phenotype with focal-onset seizures as the only seizure type. All patients showed normal psychomotor development in the first years of life, and no intellectual disability although they displayed some cognitive or behavioural problems. Fever or hyperthermia were triggers in all three patients. In addition, all had a history of brief recurrent febrile seizures in their first year, followed by a phenotype of pharmacoresistant focal epilepsy with normal brain imaging. Two of them were initially investigated for epilepsy surgery. Seizure precipitation by fever has also been reported in previously published patients. SIGNIFICANCE: Focal epilepsy associated with SCN1A gene mutation should be recognized in patients with suggestive features, in particular among surgical candidates.

Felbamate for infantile spasms syndrome resistant to first-line treatments.

AIM: To analyse the effects of felbamate in refractory infantile spasms/West syndrome. METHOD: We conducted a 10-year retrospective study of infants (including all infants younger than 18mo) treated with felbamate for electroencephalography-recorded epileptic spasms persisting after first-line treatment. RESULTS: In total, 29 infants (17 males, 12 females) were included in the study. Felbamate was initiated at a mean age of 13.8 months (range 4.5-66mo) after sequential administration or combination of vigabatrin and oral steroids; a ketogenic diet was implemented in 23 infants. Eight infants became spasm-free at a mean dose of 34.6mg/kg/day felbamate (range 26-45mg/kg/day). Mean duration of felbamate use was 19 months (range 1-67mo) for the 19 infants whose treatment was terminated. No severe side effects were observed. Reversible neutropenia led to withdrawal of felbamate in six patients. One spasm-free patient demonstrated recurrence when felbamate was withdrawn. INTERPRETATION: N-methyl-d-aspartate receptors with felbamate controlled epileptic spasms in eight infants resistant to first-line treatment should be targeted.

Paediatric-onset neuronal ceroid lipofuscinosis: first symptoms and presentation at diagnosis.

Neuronal ceroid lipofuscinoses (NCLs) are rare, progressive disorders. Through this series of 20 patients with NCL, we illustrate differences between subtypes in their presenting symptoms and clinical, imaging, and electrophysiological results to raise awareness of symptom diversity. Data were available on presenting symptoms, genetics, magnetic resonance imaging (MRI), electroencephalography (including with low-frequency intermittent photic stimulation), visual responses, and electron microscopy. Causal mutations were identified in 10 patients. Eleven patients had neuronal ceroid lipofuscinosis type 2 (CLN2) disease and their most common presenting symptom was seizures, although motor and language defects were also reported. Five patients with CLN2 disease showed abnormalities at initial MRI, but only three showed a photic response with low-frequency stimulation. Seizures were not as common a presenting symptom in other NCL subtypes. Patients with NCLs present with diverse symptoms, which may not be characteristic in early disease stages. These signs and symptoms should lead to rapid diagnostic confirmatory testing for NCLs. WHAT THIS PAPER ADDS: Disease presentation is not uniform for neuronal ceroid lipofuscinoses. Characteristic clinical test results may not be identified in early disease stages.

The epileptology of GNB5 encephalopathy.

Pathogenic variants in GNB5 cause an autosomal recessive neurodevelopmental disorder with neonatal sinus bradycardia. Seizures or epilepsy occurred in 10 of 22 previously reported cases, including 6 children from one family. We delineate the epileptology of GNB5 encephalopathy. Our nine patients, including five new patients, were from seven families. Epileptic spasms were the most frequent seizure type, occurring in eight of nine patients, and began at a median age of 3 months (2 months to 3 years). Focal seizures preceded spasms in three children, with onset at 7 days, 11 days, and 4 months. One child presented with convulsive status epilepticus at 6 months. Three children had burst suppression on electroencephalography (EEG), three had hypsarrhythmia, and one evolved from burst suppression to hypsarrhythmia. Background slowing was present in all after age 3 years. Magnetic resonance imaging (MRI) showed cerebral atrophy in one child and cerebellar atrophy in another. All nine had abnormal development prior to seizure onset and ultimately had profound impairment without regression. Hypotonia was present in all, with contractures developing in two older patients. All individuals had biallelic pathogenic variants in GNB5, predicted by in silico tools to result in protein truncation and loss-of-function. GNB5 developmental and epileptic encephalopathy is characterized by epileptic spasms, focal seizures, and profound impairment.

Early identification of epileptic encephalopathy with continuous spikes-and-waves during sleep: A case-control study.

Epileptic encephalopathy with continuous spikes-and-waves during sleep (EE-CSWS) is a rare childhood epilepsy syndrome characterized by a regression in cognitive, behavioral and psychiatric functioning, seizures and a specific electroencephalographic pattern. An early recognition and an appropriate treatment might play a key role in the outcome of this epileptic encephalopathy. We conducted a case-control study to evaluate if there is any clinical or electroencephalographic sign suggestive of EE-CSWS after the first seizure. We retrospectively identified 10 EE-CSWS patients with available EEG recordings at time of the first seizure. We matched them with 10 controls from our first seizure clinics. All EEG recording were analyzed for the study. We did not find any clinical or EEG features that would suggest later development of EE-CSWS. As reported by others, the occurrence of multiple seizures types and a seizure worsening during the follow-up is more frequent in the cases than in the controls. These clinical criteria might be used as a red flag in clinical practice to identify the very few patients with EE-CSWS among the frequent patients with BECTS.

Use of perampanel in children and adolescents with Lennox-Gastaut Syndrome.

AIM: Report the use of perampanel treatment in children with Lennox-Gastaut syndrome (LGS). METHOD: We conducted a prospective study of 13 LGS patients (seven male; mean age, 12.8years) treated with adjunctive perampanel therapy. Perampanel was initiated at 2mg/day and titrated to a median maximum dose of 6mg/day. RESULTS: After a mean follow-up duration of 10.8months (range, 1-24months), nine patients (69.2%) were responders (≥50% reduction in total seizure frequency) and nine (69.2%) were rated by their physician as "much improved" or "very much improved". Four patients (30.8%) discontinued perampanel due to the lack of efficacy (n=2) and seizure aggravation (n=2). No patients discontinued due to other adverse events (AEs). AEs were reported for six patients (46.2%) and comprised decreased activity/social interaction (n=3), behavior disturbance with agitation (n=2), and/or fatigue (n=2). All AEs became manageable after perampanel dosing was decreased. Improvements in cognitive function and/or behavior were reported for seven patients (53.8%). Introduction of perampanel allowed the dose reduction and/or discontinuation of other treatments in seven patients (53.8%). INTERPRETATION: Perampanel was efficacious and generally well tolerated as an adjunctive treatment for seizures associated with LGS, supporting further research in this area.

Myoclonic jerks are commonly associated with absence seizures in early-onset absence epilepsy.

Typical absence seizures are observed in various epilepsy syndromes, however, few series have focused on early-onset absence epilepsy (EOAE). We aimed to evaluate the occurrence of this seizure type in children under 4 years of age in order to evaluate their electroclinical characteristics and outcome. We retrospectively studied (2006-2014) the electroclinical features of children with normal development and typical absence seizures starting before the age of 4 (with available pre-treatment video-EEG). Nine patients were included. Among them, eight patients had rhythmic myoclonic jerks involving the muscles of the upper face (eyebrows and eyelids) or neck, present from the onset to the end of the typical absence discharge. The myoclonia were synchronous with spike-wave complexes. One patient with GLUT-1 deficiency was refractory to antiepileptic polytherapy. The other eight became seizure-free; five with one antiepileptic drug and three with a combination of two drugs. The treatment was successfully withdrawn in five of the six patients who achieved two years of seizure freedom. None of them exhibited any other seizure type. Four of the eight patients with normal schooling required some support. We observed a positive correlation between the duration of absence seizure and the age of the patient at examination. Most of the patients under four years with only typical absence seizures had EOAE, and the motor symptoms may represent a distinctive age-related feature of EOAE. Further investigations are required to better correlate the role of brain maturation with the duration of the absence. [Published with video sequence on www.epilepticdisorders.com].

Use of modified Atkins diet in glucose transporter type 1 deficiency syndrome.

AIM: Glucose transporter type 1 deficiency syndrome (GLUT1-DS) results from impaired glucose transport into the brain, and is treated with a ketogenic diet. A few reports have suggested effectiveness of treatment using the modified Atkins diet (MAD). We aimed to assess the efficacy of MAD as a treatment for GLUT1-DS. METHOD: We evaluated the efficacy of MAD in 10 patients (four males, six females; mean age at diagnosis [SD] 6.2y [1.7], min-max: 4mo-12y) with GLUT1-DS. RESULTS: MAD was started at diagnosis in eight patients, including two infants. The mean duration (SD) under MAD was 2.5 [0.6] years (range 6mo-6y). Seven patients with epilepsy started MAD at GLUT1-DS diagnosis, and all experienced improvements in their epilepsy: five out of seven were seizure-free at M1, and three out of six at M3 and M6. The initiation of MAD allowed symptoms to be controlled in the three patients with movement disorders but without seizures. Two patients switched from the ketogenic diet to MAD. This switch was not responsible for the recurrence of any symptoms, and led to improvements in both physical abilities and growth parameters. INTERPRETATION: MAD, which is a less restrictive and more palatable diet than the ketogenic diet, seems to have comparable effectiveness. Moreover, a switch from the ketogenic diet to MAD appears to be beneficial for patients with GLUT1-DS.

An unfortunate challenge: Ketogenic diet for the treatment of Lennox-Gastaut syndrome in tyrosinemia type 1.

The ketogenic diet is an evidence-based treatment for resistant epilepsy including Lennox-Gastaut syndrome. This diet is based on low carbohydrate-high fat intakes. Dietary treatment is also therapeutic for inborn errors of metabolism such as aminoacdiopathies. We report a child with both Lennox-Gastaut syndrome and tyrosinemia type 1. This epilepsy syndrome resulted form a porencephalic cyst secondary to brain abscesses that occurred during the management of malnutrition due to untreated tyrosinemia type 1. We used a ketogenic diet as treatment for Lennox-Gastaut syndrome taking into account dietary requirements for tyrosinemia type 1. The patient was transiently responder during a 6-month period. This report illustrates that ketogenic diet remains a therapeutic option even when additional dietary requirements are needed.

Ketogenic diet for infantile spasms refractory to first-line treatments: an open prospective study.

UNLABELLED: Ketogenic diet (KD) is an efficient treatment for refractory epilepsy including infantile spasms (IS). We evaluated the effect of a KD to treat IS as a third-line treatment, after vigabatrin (VGB) and steroids. We evaluated the efficacy and the tolerability of KD in IS using the rate of seizure-free patients at 1 month. METHODS: We conducted an open study using the data from a prospective database of two French child neurology departments (Amiens & Robert Debré-Paris, France) over a three-year period. All the patients followed the KD for 6 months. The addition of an antiepileptic drug was allowed after 1 month of KD in the non-seizure-free patients. RESULTS: 17 patients were treated by KD for IS. The KD was initiated at the mean age of 9.4±1.1 months. After 1 month with KD, 6/17 (35%) patients were seizure free while 11/17 (65%) were seizure-free after the third month. However, an additional antiepileptic drug (felbamate or topiramate) was given to all patients that were not seizure-free under KD. The KD was well tolerated. CONCLUSION: Our responder rate is similar to previous studies despite an early use (before 1-year-old) and the use of KD after VGB and steroids. The KD was well-tolerated in this population of young infants. Felbamate leads to an increase in the responder rate after the use of KD.