Expanding SPG18 clinical spectrum: autosomal dominant mutation causes complicated hereditary spastic paraplegia in a large family.

BACKGROUND: SPG18 is caused by mutations in the endoplasmic reticulum lipid raft associated 2 (ERLIN2) gene. Autosomal recessive (AR) mutations are usually associated with complicated hereditary spastic paraplegia (HSP), while autosomal dominant (AD) mutations use to cause pure SPG18. AIM: To define the variegate clinical spectrum of the SPG18 and to evaluate a dominant negative effect of erlin2 (encoded by ERLIN2) on oligomerization as causing differences between AR and AD phenotypes. METHODS: In a four-generation pedigree with an AD pattern, a spastic paraplegia multigene panel test was performed. Oligomerization of erlin2 was analyzed with velocity gradient assay in fibroblasts of the proband and healthy subjects. RESULTS: Despite the common p.V168M mutation identified in ERLIN2, a phenoconversion to amyotrophic lateral sclerosis (ALS) was observed in the second generation, pure HSP in the third generation, and a complicated form with psychomotor delay and epilepsy in the fourth generation. Erlin2 oligomerization was found to be normal. DISCUSSION: We report the first AD SPG18 family with a complicated phenotype, and we ruled out a dominant negative effect of V168M on erlin2 oligomerization. Therefore, our data do not support the hypothesis of a relationship between the mode of inheritance and the phenotype, but confirm the multifaceted nature of SPG18 on both genetic and clinical point of view. Clinicians should be aware of the importance of conducting an in-depth clinical evaluation to unmask all the possible manifestations associated to an only apparently pure SPG18 phenotype. We confirm the genotype-phenotype correlation between V168M and ALS emphasizing the value of close follow-up.

Perampanel Improves Cortical Myoclonus and Disability in Progressive Myoclonic Epilepsies: A Case Series and a Systematic Review of the Literature.

Introduction: Progressive myoclonic epilepsies (PMEs) are a heterogenous group of genetic diseases presenting with epilepsy, cognitive impairment, and severe action myoclonus, which can severely affect daily life activities and independent walking ability. Perampanel is a recent commercially available antiseizure medication with high efficacy against generalized seizures. Some reports supported the role of perampanel in ameliorating action myoclonus in PMEs. Here, we aimed to describe a case series and provide a systematic literature review on perampanel effects on PMEs. Methods: We report the perampanel effectiveness on myoclonus, daily life activities, and seizures on an original Italian multicenter case series of 11 individuals with PMEs. Then, using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, we performed a systematic review on perampanel effect on myoclonus and disability in PMEs. We searched PubMed, Scopus, and Google Scholar articles on perampanel and PMEs up to June 2020. No prospective trials were found. We reviewed 11 case series manuscripts reporting 104 cases of different PMEs. Results: Here, we are reporting the effectiveness of perampanel in five individuals affected by Unverricht-Lundborg disease, three by Lafora disease, two by sialidosis, and one by an undetermined PME. Nine out of 11 individuals improved their disability related to the action myoclonus (two with Lafora disease did not). Among the 104 persons with PMEs collected by the systematic review, we found that more than half of the patients receiving perampanel exhibited an amelioration of action myoclonus and, consequently, of their independence in daily life activities. The Unverricht-Lundborg disease seemed to show the best clinical response to perampanel, in comparison with the other more severe PMEs. A significant seizure reduction was achieved by almost all persons with active epilepsy. Only 11% of PME patients dropped out due to inefficacy. Conclusions: Perampanel demonstrated a beneficial effect with regard to action myoclonus, disability, and seizures and was well-tolerated in people with PMEs, independently from their genetic diagnosis. Given the limited scientific evidence, broader prospective trials should be encouraged.

Eyelid myoclonia with absences: an overlooked epileptic syndrome?

AIM: To identify, among patients referred to our Epilepsy Center, those fulfilling eyelid myoclonia with absences (EMA) criteria and to evaluate their semiological, electroclinical and evolutive features. In addition, to examine some possible causes of underdiagnosis and to stress the role of video-EEG (VEEG) recording. MATERIALS AND METHODS: Retrospective analysis of 2780 epileptic patients. INCLUSION CRITERIA: Eyelid myoclonia and brief absences, related to EEG generalized paroxysmal activity and triggered by eye closure and/or by intermittent photic stimulation. RESULTS: 7.46% of our patients with idiopathic generalized epilepsy (IGE) could be classified as EMA. Female/male ratio was 1.7:1. Familial history of epilepsy was present in about half of the patients, with two pairs of identical twins in the sample. Rare generalized tonic-clonic seizures occurred in most cases. CONCLUSIONS: EMA is a not infrequent condition among IGEs. It is likely to be underdiagnosed due to the subtle clinical semiology and to masking of EEG changes by the effects of age and anti-epileptic drugs. VEEG analysis is often needed for diagnosis of EMA. Most likely, only genetic research will be able to clarify whether EMA is a distinct epileptic syndrome.

Tiagabine in glial tumors.

RATIONALE AND PURPOSE: Preliminary reports have suggested a possible 'aetiology-specific' efficacy of tiagabine (TGB) in patients with drug-resistant partial epilepsy (DRPE) related to cerebral glial tumors (GTs). This efficacy should be related to selective blocking of GAT-1 transporter by TGB. We presented our open-label, add-on TGB experience in a group of patients with GTs, compared with other symptomatic DRPEs of different aetiology. MATERIAL AND METHODS: eleven patients with DRPE related to oligodendroglioma (six cases), astrocytoma (4) or multiform gliobastoma (1); 12 patients with DRPE related to a miscellanea of CNS lesions. TGB was added to previous AEDs, at dosage of 20-60 mg per die. Responders are defined by seizure frequency reduction >50% compared with baseline. RESULTS: Seven patients are responders with three seizure-free (SF) in GTs group, a rate of efficacy much higher than in matching group (63.6 vs. 16.6%). Adverse events have been observed only rarely, not leading to discontinuation, in GTs group. CONCLUSION: This preliminary observation seems to confirm the high efficacy and tolerability of TGB in DRPE related to GTs.