Probability of Remission of the Main Epileptic Syndromes in Childhood

Aim To determine the long-term probability of remission without antiepileptic treatment of common epileptic syndromes and of children without a specific syndromic diagnosis. Patients and methods All children less than 14 years old with 2 or more unprovoked seizures seen at our hospital between June 1, 1994, and March 1, 2011 (n = 680), were included and prospectively followed up until August 15, 2020. Syndromic diagnosis was made retrospectively but blinded to subsequent evolution, employing the data available at 6 months after diagnosis and under predefined operational criteria. Results The Kaplan-Meier estimate of the probability of achieving a remission period of at least 5 years, with neither seizures nor antiepileptic treatment at 14 years was 97% for well-defined childhood epilepsy with centrotemporal spikes, 82% for uncertain childhood epilepsy with centrotemporal spikes, 85% for well-defined Panayiotopoulos syndrome, 88% for uncertain Panayiotopoulos syndrome, 93% for nonfamilial self-limited infantile epilepsy, 100% for familial self-limited infantile epilepsy, 86% for absence epilepsy, 6% for juvenile myoclonic epilepsy, 71% for cryptogenic West syndrome, 72% for patients with no associated neurologic deficits and no specific syndromic diagnosis, 65% for symptomatic West syndrome, and 40% for patients with associated neurologic deficits and no specific syndromic diagnosis. Conclusions The study results highlight the long-term outcomes of the main epileptic syndromes and also of the patients with no syndromic diagnosis.

A New Case of de novo Variant c.892C>T (p.Arg298Trp) in NACC1: A First Case Report From China

Background: The nucleus accumbens associated 1 (NACC1) gene is a transcription factor member of the BTB/POZ family. A de novo heterozygous c.892C>T (p.Arg298Trp) variant in the NACC1 may define a syndrome characterized by intellectual disability, infantile epilepsy, congenital cataract, and feeding difficulties.Case Presentation: We report a new case with a neurodevelopmental disorder characterized by severe intellectual disability, infantile epilepsy, congenital cataract, and feeding difficulties. Brain MRI reveals brain dysplasia. We observe a de novo heterozygous c.892C>T (p.Arg298Trp) variant in the NACC1 gene in this case. Now, the child regularly goes to the hospital for rehabilitation training (once a month). Sodium Valproate (10 mg/kg/day) and Clobazam (10 mg/kg/day) are used in the treatment of epilepsy. A total of three articles were screened, and two papers were excluded. The search revealed one article related to a syndrome caused by a de novo heterozygous c.892C>T (p.Arg298Trp) variant in the NACC1; they screened the main clinical features of eight cases of a syndrome, which were summarized and analyzed.Conclusions: The NACC1 gene is a member of the BTB/POZ family of transcription factors. A de novo heterozygous c.892C>T (p.Arg298Trp) variant in the NACC1 may define a syndrome characterized by intellectual disability, infantile epilepsy, congenital cataract, and feeding difficulties. At present, there is no effective cure. In the future, we need more cases to determine the phenotype–genotype correlation of NACC1 variants. Many questions remain to be answered, and many challenges remain to be faced. Future transcriptional studies may further clarify this rare, recurrent variant, and could potentially lead to targeted therapies.

PRRT2 Related Epilepsies: A Gene Review

PRRT2 encodes for proline-rich transmembrane protein 2 involved in synaptic vesicle fusion and presynaptic neurotransmitter release. Mutations in human PRRT2 have been related to paroxysmal kinesigenic dyskinesia (PKD), infantile convulsions with choreoathetosis, benign familial infantile epilepsies, and hemiplegic migraine. PRRT2 mutations cause neuronal hyperexcitability, which could be related to basal ganglia or cortical circuits dysfunction, leading to paroxysmal disorders. PRRT2 is expressed in the cerebral cortex, basal ganglia, and cerebellum. Approximately, 90% of pathogenic variants are inherited and 10% are de novo. Paroxysmal attacks in PKD are characterized by dystonia, choreoathetosis, and ballismus. In the benign familial infantile epilepsy (BFIE), seizures are usually focal with or without generalization, usually begin between 3 and 12 months of age and remit by 2 years of age. In 30% of cases of PRRT2-associated PKD, there is an association with BFIE, and this entity is referred to as PKD with infantile convulsions (PKD/IC). PRRT2 mutations are the cause of benign family childhood epilepsy and PKD/IC. On the other hand, PRRT2 mutations do not seem to correlate with other types of epilepsy. The increasing incidence of hemiplegic migraine in families with PRRT2-associated PKD or PKD/IC suggests a common disease pathway, and it is possible to assert that BFIE, paroxysmal kinesigenic dyskinesia, and PKD with IC belong to a continuous disease spectrum of PRRT2-associated diseases.