Spectrum of ERCC6-Related Cockayne Syndrome (Type B): From Mild to Severe Forms

(1) Background: Cockayne syndrome (CS) is an ultra-rare multisystem disorder, classically subdivided into three forms and characterized by a clinical spectrum without a clear genotype-phenotype correlation for both the two causative genes ERCC6 (CS type B) and ERCC8 (CS type A). We assessed this, presenting a series of patients with genetically confirmed CSB. (2) Materials and Methods: We retrospectively collected demographic, clinical, genetic, neuroimaging, and serum neurofilament light-chain (sNFL) data about CSB patients; diagnostic and severity scores were also determined. (3) Results: Data of eight ERCC6/CSB patients are presented. Four patients had CS I, three patients CS II, and one patient CS III. Various degrees of ataxia and spasticity were cardinal neurologic features, with variably combined systemic characteristics. Mean age at diagnosis was lower in the type II form, in which classic CS signs were more evident. Interestingly, sNFL determination appeared to reflect clinical classification. Two novel premature stop codon and one novel missense variants were identified. All CS I subjects harbored the p.Arg735Ter variant; the milder CS III subject carried the p.Leu764Ser missense change. (4) Conclusion: Our work confirms clinical variability also in the ERCC6/CSB type, where manifestations may range from severe involvement with prenatal or neonatal onset to normal psychomotor development followed by progressive ataxia. We propose, for the first time in CS, sNFL as a useful peripheral biomarker, with increased levels compared to currently available reference values and with the potential ability to reflect disease severity.

Evolution of neuropsychological and behavioral profile in a cohort of pediatric patients with Becker muscular dystrophy in a longitudinal study

It has long been reported that neuropsychological deficits may be present in dystrophinopathies, specifically non-progressive cognitive impairment and a global deficit in executive functions; this neurocognitive profile has been less explored in patients with Becker than Duchenne muscular dystrophy (BMD/DMD). We conducted a longitudinal study to explore the evolution of neuropsychological and behavioural profile in a cohort of paediatric BMD. Seventeen patients with BMD without intellectual disability were assessed using a full battery of tests, including intellectual, adaptive and executive functioning, language and behavioral features. Tests were performed at baseline and after 12 months. The results showed adequate cognitive and adaptive profile with falls in Working Memory, as well as lower scores in executive functions. An improvement was observed in Processing Speed. Behavioral questionnaires confirmed a negative trend, while in normal ranges. We found a statistically significant difference between T0 and T1 in some items exploring executive functions. No statistically significant difference was observed stratifying patients by mutation site or IQ level. In conclusion, our study suggests that BMD patients have a stable neurocognitive profile, while a deflection in the executive functions may be observed. We recommend a careful monitoring to intercept learning disabilities and promptly start a multimodal rehabilitation.

Aspiration thrombectomy of M2 segment in acute ischemic stroke: The clinical reality in a neurovascular reference center

OBJECTIVE

Our study aimed to evaluate safety, efficacy and clinical outcomes in patients with acute ischemic stroke with occlusion of M2 segment treated with thromboaspiration.

MATERIALS AND METHODS

A retrospective study was conducted in patients with ischemic stroke of M2 segment undergoing endovascular thromboaspiration. The time period analyzed was from October 2015 until February 2021. Thromboaspiration was performed with AXS Catalyst 5 (Stryker) or AXS Catalyst 6 (Stryker) catheters. The following parameters were assessed: risk factors for ischemic stroke, National Institutes of Health Stroke Scale (entry and discharge), pre-procedural fibrinolysis, pre-procedural and 24-h Alberta Stroke Program Early CT Score, recanalization time, number of passages for recanalization, Thrombolysis in cerebral infarction scale score, periprocedural complications, Modified Rankin Scale score at 90 days from procedure and mortality.

RESULTS

90 patients were included in the study. The mean age was 75 ± 11.1 with National Institutes of Health Stroke Scale at entry 13 ± 5 and 8 ± 4 at discharge. Pre-procedural fibrinolysis were performed in 40 patients. Pre-procedural Alberta Stroke Program Early CT Score were 8.8 ± 1.3 and 6.9 ± 2.4 after 24 h from the procedure. Time of recanalization from onset of symptoms was 300 ± 82 min. Number of passages for recanalization were 1.8 ± 1.1. Thrombolysis in cerebral infarction scale score ≥ 2b were obtained in 90 % of procedures. After 90 days 33 % of patient obtained an Modified Rankin Scale between 0 and 1 (between 0 and 2 was 40 %). We didn't detect any complication in 64 % of cases (subarachnoid haemorrhage in 2 %, HI1 and HI 2 in 15 %, PH1 in 9 % of patients, PH2 in 6 % of patients).

CONCLUSIONS

This paper confirms the usefulness and safety of thrombospiration in patients with ischemic stroke in the M2 segment with low intra-operative risks, high technical success and positive impact on the outcome of the patients.

White matter abnormalities in 15 subjects with SPG76

BACKGROUND AND OBJECTIVES

Hereditary spastic paraplegias (HSPs) are heterogenous genetic disorders characterized by progressive pyramidal tract involvement. SPG76 is a recently identified form of HSP, caused by biallelic calpain-1 (CAPN1) variants. The most frequently described MRI abnormality in SPG76 is mild cerebellar atrophy and non-specific white matter abnormalities were reported in only one case. Following the identification of prominent white matter abnormalities in a subject with CAPN1 variants, which delayed the diagnosis, we aimed to verify the presence of MRI patterns of white matter involvement specific to this HSP.

METHODS

We performed a retrospective radiological qualitative analysis of 15 subjects with SPG76 (4 previously unreported) initially screened for white matter involvement. Moreover, we performed quantitative analyses in our proband with available longitudinal studies.

RESULTS

We observed bilateral, periventricular white matter involvement in 12 subjects (80%), associated with multifocal subcortical abnormalities in 5 of them (33.3%). Three subjects (20%) presented only multifocal subcortical involvement. Longitudinal quantitative analyses of our proband revealed increase in multifocal white matter lesion count and increased area of periventricular white matter involvement over time.

DISCUSSION

SPG76 should be added to the list of HSPs with associated white matter abnormalities. We identified periventricular white matter involvement in subjects with SPG76, variably associated with multifocal subcortical white matter abnormalities. These findings, in the presence of progressive spastic paraparesis, can mislead the diagnostic process towards an acquired white matter disorder.

A New Case of Autosomal-Dominant POLR3B-Related Disorder: Widening Genotypic and Phenotypic Spectrum

POLR3B encodes the RPC2 subunit of RNA polymerase III. Pathogenic variants are associated with biallelic hypomyelinating leukodystrophy belonging to the POLR-related disorders. Recently, the association with dominant demyelinating neuropathy, classified as Charcot-Marie-Tooth syndrome type 1I (CMT1I), has been reported as well. Here we report on an additional patient presenting with developmental delay and generalized epilepsy, followed by the onset of mild pyramidal and cerebellar signs, vertical gaze palsy and subclinical demyelinating polyneuropathy. A new heterozygous de novo missense variant, c.1297C > G, p.Arg433Gly, in POLR3B was disclosed via trio-exome sequencing. In silico analysis confirms the hypothesis on the variant pathogenicity. Our research broadens both the genotypic and phenotypic spectrum of the autosomal-dominant POLR3B-related condition.

Extreme phenotypic heterogeneity in non-expansion spinocerebellar ataxias

Although the best-known spinocerebellar ataxias (SCAs) are triplet repeat diseases, many SCAs are not caused by repeat expansions. The rarity of individual non-expansion SCAs, however, has made it difficult to discern genotype-phenotype correlations. We therefore screened individuals who had been found to bear variants in a non-expansion SCA-associated gene through genetic testing, and after we eliminated genetic groups that had fewer than 30 subjects, there were 756 subjects bearing single-nucleotide variants or deletions in one of seven genes: CACNA1A (239 subjects), PRKCG (175), AFG3L2 (101), ITPR1 (91), STUB1 (77), SPTBN2 (39), or KCNC3 (34). We compared age at onset, disease features, and progression by gene and variant. There were no features that reliably distinguished one of these SCAs from another, and several genes-CACNA1A, ITPR1, SPTBN2, and KCNC3-were associated with both adult-onset and infantile-onset forms of disease, which also differed in presentation. Nevertheless, progression was overall very slow, and STUB1-associated disease was the fastest. Several variants in CACNA1A showed particularly wide ranges in age at onset: one variant produced anything from infantile developmental delay to ataxia onset at 64 years of age within the same family. For CACNA1A, ITPR1, and SPTBN2, the type of variant and charge change on the protein greatly affected the phenotype, defying pathogenicity prediction algorithms. Even with next-generation sequencing, accurate diagnosis requires dialogue between the clinician and the geneticist.

Antioxidant Response in Human X-Linked Adrenoleukodystrophy Fibroblasts

Redox imbalance, mitochondrial dysfunction, and inflammation play a major role in the pathophysiology of X-linked adrenoleukodystrophy (X-ALD), an inherited neurodegenerative disease caused by mutations in the ABCD1 gene, encoding the protein responsible for peroxisomal import and degradation of very long chain fatty acids (VLCFAs). Therefore, VLCFAs accumulate in tissues and plasma, constituting a pathognomonic biomarker for diagnosis. However, the precise role of VLCFA accumulation on the diverse clinical phenotypes of X-ALD and the pathogenic link between VLCFAs and oxidative stress remain currently unclear. This study proposes ferroptosis as a crucial contributor to the disease development and progression. The expression profiles of "GPX4-glutathione" and "NQO1-CoQ₁₀" ferroptosis pathways have been analyzed in fibroblasts of one patient with AMN, the late onset and slowly progressive form of X-ALD, and in two patients with cALD, the cerebral inflammatory demyelinating form of early childhood. Furthermore, as no effective treatments are currently available, especially for the rapidly progressing form of X-ALD (cALD), the efficacy of NAC treatment has also been evaluated to open the way toward novel combined therapies. Our findings demonstrate that lipid peroxides accumulate in X-ALD fibroblasts and ferroptosis-counteracting enzymes are dysregulated, highlighting a different antioxidant response in patients with AMN and cALD.

Biallelic Variants in the Ectonucleotidase ENTPD1 Cause a Complex Neurodevelopmental Disorder with Intellectual Disability, Distinct White Matter Abnormalities, and Spastic Paraplegia

OBJECTIVE

Human genomics established that pathogenic variation in diverse genes can underlie a single disorder. For example, hereditary spastic paraplegia is associated with >80 genes, with frequently only few affected individuals described for each gene. Herein, we characterize a large cohort of individuals with biallelic variation in ENTPD1, a gene previously linked to spastic paraplegia 64 (Mendelian Inheritance in Man # 615683).

METHODS

Individuals with biallelic ENTPD1 variants were recruited worldwide. Deep phenotyping and molecular characterization were performed.

RESULTS

A total of 27 individuals from 17 unrelated families were studied; additional phenotypic information was collected from published cases. Twelve novel pathogenic ENTPD1 variants are described (NM 001776.6): c.398_399delinsAA; p.(Gly133Glu), c.540del; p.(Thr181Leufs*18), c.640del; p.(Gly216Glufs*75), c.185 T > G; p.(Leu62*), c.1531 T > C; p.(*511Glnext*100), c.967C > T; p.(Gln323*), c.414-2_414-1del, and c.146 A > G; p.(Tyr49Cys) including 4 recurrent variants c.1109 T > A; p.(Leu370*), c.574-6_574-3del, c.770_771del; p.(Gly257Glufs*18), and c.1041del; p.(Ile348Phefs*19). Shared disease traits include childhood onset, progressive spastic paraplegia, intellectual disability (ID), dysarthria, and white matter abnormalities. In vitro assays demonstrate that ENTPD1 expression and function are impaired and that c.574-6_574-3del causes exon skipping. Global metabolomics demonstrate ENTPD1 deficiency leads to impaired nucleotide, lipid, and energy metabolism.

INTERPRETATION

The ENTPD1 locus trait consists of childhood disease onset, ID, progressive spastic paraparesis, dysarthria, dysmorphisms, and white matter abnormalities, with some individuals showing neurocognitive regression. Investigation of an allelic series of ENTPD1 (1) expands previously described features of ENTPD1-related neurological disease, (2) highlights the importance of genotype-driven deep phenotyping, (3) documents the need for global collaborative efforts to characterize rare autosomal recessive disease traits, and (4) provides insights into disease trait neurobiology. ANN NEUROL 2022;92:304-321.

Clinical-Genetic Features Influencing Disability in Spastic Paraplegia Type 4

Background and Objectives

Hereditary spastic paraplegias (HSPs) are a group of inherited rare neurologic disorders characterized by length-dependent degeneration of the corticospinal tracts and dorsal columns, whose prominent clinical feature is represented by spastic gait. Spastic paraplegia type 4 (SPG4, SPAST-HSP) is the most common form. We present both clinical and molecular findings of a large cohort of patients, with the aim of (1) defining the clinical spectrum of SPAST-HSP in Italy; (2) describing their molecular features; and (3) assessing genotype-phenotype correlations to identify features associated with worse disability.

Methods

A cross-sectional retrospective study with molecular and clinical data collected in an anonymized database was performed.

Results

A total of 723 Italian patients with SPAST-HSP (58% men) from 316 families, with a median age at onset of 35 years, were included. Penetrance was 97.8%, with men showing higher Spastic Paraplegia Rating Scale (SPRS) scores (19.67 ± 12.58 vs 16.15 ± 12.61, p = 0.009). In 26.6% of patients with SPAST-HSP, we observed a complicated phenotype, mainly including intellectual disability (8%), polyneuropathy (6.7%), and cognitive decline (6.5%). Late-onset cases seemed to progress more rapidly, and patients with a longer disease course displayed a more severe neurologic disability, with higher SPATAX (3.61 ± 1.46 vs 2.71 ± 1.20, p < 0.001) and SPRS scores (22.63 ± 11.81 vs 12.40 ± 8.83, p < 0.001). Overall, 186 different variants in the SPAST gene were recorded, of which 48 were novel. Patients with SPAST-HSP harboring missense variants displayed intellectual disability (14.5% vs 4.4%, p < 0.001) more frequently, whereas patients with truncating variants presented more commonly cognitive decline (9.7% vs 2.6%, p = 0.001), cerebral atrophy (11.2% vs 3.4%, p = 0.003), lower limb spasticity (61.5% vs 44.5%), urinary symptoms (50.0% vs 31.3%, p < 0.001), and sensorimotor polyneuropathy (11.1% vs 1.1%, p < 0.001). Increasing disease duration (DD) and abnormal motor evoked potentials (MEPs) were also associated with increased likelihood of worse disability (SPATAX score>3).

Discussion

The SPAST-HSP phenotypic spectrum in Italian patients confirms a predominantly pure form of HSP with mild-to-moderate disability in 75% of cases, and slight prevalence of men, who appeared more severely affected. Early-onset cases with intellectual disability were more frequent among patients carrying missense SPAST variants, whereas patients with truncating variants showed a more complicated disease. Both longer DD and altered MEPs are associated with worse disability.

Novel SEPSECS Pathogenic Variants Featuring Unusual Phenotype of Complex Movement Disorder With Thin Corpus Callosum: A Case Report

Objectives

To report a novel association between pathogenic variants in the SEPSECS gene and complex movement disorder with thin corpus callosum (TCC).

Methods

Clinical exome sequencing was performed in an adult patient with a genetically unsolved neurodegenerative disorder. The main clinical, neuroimaging, and genetic data were described.

Results

The c.865C > T (p.P289S) and c.1297T > C (p.Y433H) missense variants in SEPSECS (NM_016,955.3) were discovered.

Discussion

This case represents a novel form of early-onset pyramidal syndrome with optic nerve hypoplasia, which slowly evolved to extrapyramidal syndrome featuring dystonia-parkinsonism, associated with TCC, caused by SEPSECS pathogenic variants. This form enlarges the group of the so-called pyramidal-extrapyramidal syndromes, as well as complex hereditary spastic paraparesis with TCC.

Neurological and Neuroimaging Features of CYB5R3-Related Recessive Hereditary Methemoglobinemia Type II

Recessive hereditary methemoglobinemia (RHM) due to NADH-cytochrome b5 reductase deficiency is a rare disease caused by pathogenic variants in CYB5R3. Unlike type I, in RHM type II (RHM2), the enzymatic defect affects erythrocytes and all body tissues, thus resulting in cyanosis and neurological impairment. Although the first description of RHM2 dates back to the mid-1950s, detailed clinical and neuroimaging information are available for only a few patients. Here, we describe a new patient with RHM2 that harbors an unreported homozygous 31 Kb deletion involving part of CYB5R3, and showing a peculiar neuroimaging pattern resembling a ponto-cerebellar hypoplasia-like condition. A careful review of the available literature was performed with the aim of better delineating neurological and neuroimaging as well as the genotypic spectra of this extremely rare disease.

Pediatric Moyamoya Disease and Syndrome in Italy: A Multicenter Cohort

BACKGROUND

Moyamoya is a rare progressive cerebral arteriopathy, occurring as an isolated phenomenon (moyamoya disease, MMD) or associated with other conditions (moyamoya syndrome, MMS), responsible for 6-10% of all childhood strokes and transient ischemic attacks (TIAs).

METHODS

We conducted a retrospective multicenter study on pediatric-onset MMD/MMS in Italy in order to characterize disease presentation, course, management, neuroradiology, and outcome in a European country.

RESULTS

A total of 65 patients (34/65 women) with MMD (27/65) or MMS (38/65) were included. About 18% (12/65) of patients were asymptomatic and diagnosed incidentally during investigations performed for an underlying condition (incMMS), whereas 82% (53/65) of patients with MMD or MMS were diagnosed due to the presence of neurological symptoms (symptMMD/MMS). Of these latter, before diagnosis, 66% (43/65) of patients suffered from cerebrovascular events with or without other manifestations (ischemic stroke 42%, 27/65; TIA 32%, 21/65; and no hemorrhagic strokes), 18% (12/65) of them reported headache (in 4/12 headache was not associated with any other manifestation), and 26% (17/65) of them experienced multiple phenotypes (≥2 among: stroke/TIA/seizures/headache/others). Neuroradiology disclosed ≥1 ischemic lesion in 67% (39/58) of patients and posterior circulation involvement in 51% (30/58) of them. About 73% (47/64) of patients underwent surgery, and 69% (45/65) of them received aspirin, but after diagnosis, further stroke events occurred in 20% (12/61) of them, including operated patients (11%, 5/47). Between symptom onset and last follow-up, the overall patient/year incidence of stroke was 10.26% (IC 95% 7.58-13.88%). At last follow-up (median 4 years after diagnosis, range 0.5-15), 43% (26/61) of patients had motor deficits, 31% (19/61) of them had intellectual disability, 13% (8/61) of them had epilepsy, 11% (7/61) of them had behavioral problems, and 25% (13/52) of them had mRS > 2. The proportion of final mRS > 2 was significantly higher in patients with symptMMD/MMS than in patients with incMMS (p = 0.021). Onset age <4 years and stroke before diagnosis were significantly associated with increased risk of intellectual disability (p = 0.0010 and p = 0.0071, respectively) and mRS > 2 at follow-up (p = 0.0106 and p = 0.0009, respectively).

CONCLUSIONS

Moyamoya is a severe condition that may affect young children and frequently cause cerebrovascular events throughout the disease course, but may also manifest with multiple and non-cerebrovascular clinical phenotypes including headache (isolated or associated with other manifestations), seizures, and movement disorder. Younger onset age and stroke before diagnosis may associate with increased risk of worse outcome (final mRS > 2).

Movement disorders in MCT8 deficiency/Allan-Herndon-Dudley Syndrome

BACKGROUND AND OBJECTIVES

MCT8 deficiency is a rare genetic leukoencephalopathy caused by a defect of thyroid hormone transport across cell membranes, particularly through blood brain barrier and into neural cells. It is characterized by a complex neurological presentation, signs of peripheral thyrotoxicosis and cerebral hypothyroidism. Movement disorders (MDs) have been frequently mentioned in this condition, but not systematically studied.

METHODS

Each patient recruited was video-recorded during a routine outpatient visit according to a predefined protocol. The presence and the type of MDs were evaluated. The type of MD was blindly scored by two child neurologists experts in inherited white matter diseases and in MD. Dystonia was scored according to Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS). When more than one MD was present, the predominant one was scored.

RESULTS

27 patients were included through a multicenter collaboration. In many cases we saw a combination of different MDs. Hypokinesia was present in 25/27 patients and was the predominant MD in 19. It was often associated with hypomimia and global hypotonia. Dystonia was observed in 25/27 patients, however, in a minority of cases (5) it was deemed the predominant MD. In eleven patients, exaggerated startle reactions and/or other paroxysmal non-epileptic events were observed.

CONCLUSION

MDs are frequent clinical features of MCT8 deficiency, possibly related to the important role of thyroid hormones in brain development and functioning of normal dopaminergic circuits of the basal ganglia. Dystonia is common, but usually mild to moderate in severity, while hypokinesia was the predominant MD in the majority of patients.

A nationwide study on Sydenham's chorea: Clinical features, treatment and prognostic factors

OBJECTIVES

Sydenham's Chorea (SC) is a neuropsychiatric disorder and a major manifestation of acute rheumatic fever. The erroneous assumption that SC is a benign and self-limiting disease, has led to a lack of high-quality scientific evidence of the therapeutical and prognostic features of SC.

STUDY DESIGN

We retrospectively analyzed the medical records of patients <18-years old with SC in 17 Italian pediatric centers. Recorded data included clinical, instrumental and laboratory parameters. Prognostic risk factors including treatment regimens were assessed with univariate and multivariate sub-analysis.

RESULTS

We included 171 patients with SC. 66% had generalized chorea, and 34% hemichorea. 81% had carditis (subclinical in 65%). Additional neurological symptoms were reported in 60% of the patients, mainly dysarthria and dysgraphia. 51% had neuropsychiatric symptoms at onset, which persisted after 12 months in 10%. Among psychiatric manifestations, the most common was anxiety disorder/depression (77%). Neurological remission was reached by 93% of the patients at 6 months; 9% relapsed. Patients were treated as follows: 11% penicillin alone, 37% immunomodulatory therapy, 16% symptomatic drugs (i.e. anti-seizure medication, dopamine antagonists) and 37% both symptomatic and immunomodulatory treatment. Neurological outcome did not differ between groups. Patients receiving symptomatic drugs had a higher risk of relapse on multivariate analysis (p = 0.045).

CONCLUSIONS

Treatment of SC was largely heterogeneous. Based on our results, immunomodulatory therapy did not show higher efficacy at medium term, although it was associated to a slightly lower risk of relapse compared to symptomatic therapy. Longitudinal studies are needed to assess specific risk factors and best treatment options.

Alexander disease evolution over time: data from an Italian cohort of pediatric-onset patients

Alexander disease (AxD) is a leukodystrophy that primarily affects astrocytes and is caused by dominant variants in the Glial Fibrillary Acidic Protein gene. Three main classifications are currently used, the traditional one defined by the age of onset, and two more recent ones based on both clinical features at onset and brain MRI findings. In this study, we retrospectively included patients with genetically confirmed pediatric-onset AxD. Twenty-one Italian patients were enrolled, and we revised all their clinical and radiological data. Participants were divided according to the current classification systems. We qualitatively analyzed data on neurodevelopment and neurologic decline in order to identify the possible trajectories of the evolution of the disease over time. One patient suffered from a Neonatal presentation and showed a rapidly evolving course which led to death within the second year of life (Type Ia). 16 patients suffered from the Infantile presentation: 5 of them (here defined Type Ib) presented developmental delay and began to deteriorate by the age of 5. A second group (Type Ic) included patients who presented a delay in neuromotor development and started deteriorating after 6 years of age. A third group (Type Id) included patients who presented developmental delay and remained clinically stable beyond adolescence. In 4 patients, the age at last evaluation made it not possible to ascertain whether they belonged to Type Ic or Id, as they were too young to evaluate their neurologic decline. 4 patients suffered from the Juvenile presentation: they had normal neuromotor development with no or only mild cognitive impairment; the subsequent clinical evolution was similar to Type Ic AxD in 2 patients, to Id group in the other 2. In conclusion, our results confirm previously described findings about clinical features at onset; based on follow-up data we might classify patients with Type I AxD into four subgroups (Ia, Ib, Ic, Id). Further studies will be needed to confirm our results and to better highlight the existence of clinical and neuroradiological prognostic factors able to predict disease progression.

Phenotypic expansion of CACNA1C-associated disorders to include isolated neurological manifestations

PURPOSE

CACNA1C encodes the alpha-1-subunit of a voltage-dependent L-type calcium channel expressed in human heart and brain. Heterozygous variants in CACNA1C have previously been reported in association with Timothy syndrome and long QT syndrome. Several case reports have suggested that CACNA1C variation may also be associated with a primarily neurological phenotype.

METHODS

We describe 25 individuals from 22 families with heterozygous variants in CACNA1C, who present with predominantly neurological manifestations.

RESULTS

Fourteen individuals have de novo, nontruncating variants and present variably with developmental delays, intellectual disability, autism, hypotonia, ataxia, and epilepsy. Functional studies of a subgroup of missense variants via patch clamp experiments demonstrated differential effects on channel function in vitro, including loss of function (p.Leu1408Val), neutral effect (p.Leu614Arg), and gain of function (p.Leu657Phe, p.Leu614Pro). The remaining 11 individuals from eight families have truncating variants in CACNA1C. The majority of these individuals have expressive language deficits, and half have autism.

CONCLUSION

We expand the phenotype associated with CACNA1C variants to include neurodevelopmental abnormalities and epilepsy, in the absence of classic features of Timothy syndrome or long QT syndrome.

Expanded phenotype of AARS1-related white matter disease

PURPOSE

Recent reports of individuals with cytoplasmic transfer RNA (tRNA) synthetase-related disorders have identified cases with phenotypic variability from the index presentations. We sought to assess phenotypic variability in individuals with AARS1-related disease.

METHODS

A cross-sectional survey was performed on individuals with biallelic variants in AARS1. Clinical data, neuroimaging, and genetic testing results were reviewed. Alanyl tRNA synthetase (AlaRS) activity was measured in available fibroblasts.

RESULTS

We identified 11 affected individuals. Two phenotypic presentations emerged, one with early infantile-onset disease resembling the index cases of AARS1-related epileptic encephalopathy with deficient myelination (n = 7). The second (n = 4) was a later-onset disorder, where disease onset occurred after the first year of life and was characterized on neuroimaging by a progressive posterior predominant leukoencephalopathy evolving to include the frontal white matter. AlaRS activity was significantly reduced in five affected individuals with both early infantile-onset and late-onset phenotypes.

CONCLUSION

We suggest that variants in AARS1 result in a broader clinical spectrum than previously appreciated. The predominant form results in early infantile-onset disease with epileptic encephalopathy and deficient myelination. However, a subgroup of affected individuals manifests with late-onset disease and similarly rapid progressive clinical decline. Longitudinal imaging and clinical follow-up will be valuable in understanding factors affecting disease progression and outcome.

Age-related sensory neuropathy in patients with spinal muscular atrophy type 1

INTRODUCTION/AIMS

Spinal muscular atrophy type 1 (SMA 1) is a devastating motor neuron disorder that leads to progressive muscle weakness, respiratory failure and premature death. Although sensory electrophysiological changes have been anecdotally found in pediatric SMA 1 patients, the age of onset of sensory neuropathy remains unknown.

METHODS

Sensory nerve conduction studies of the median and sural nerves were performed in 28 consecutive SMA 1 patients of different ages. Sensory nerve conduction velocities and sensory nerve action potential (SNAP) amplitudes recorded in these patients were compared with those obtained from 93 healthy subjects stratified by age.

RESULTS

SNAP amplitudes decreased with increasing age in the sural and median nerves, without any significant difference between upper and lower limbs.

DISCUSSION

Our data suggest that sural and median nerve SNAP amplitudes are normal in younger patients, while an axonal neuropathy appears in older ones.

PIGQ-Related Glycophosphatidylinositol Deficiency Associated with Nonprogressive Congenital Ataxia

The glycophosphatidylinositol (GPI) anchor pathway plays an essential role in posttranslational modification of proteins to facilitate proper membrane anchoring and trafficking to lipid rafts, which is critical for many cell functions, including embryogenesis and neurogenesis. GPI biosynthesis is a multi-step process requiring the activity of over 25 distinct genes, most of them belonging to the phosphatidylinositol glycan (PIG) family and associated with rare neurodevelopmental disorders. PIGQ encodes the phosphatidylinositol glycan class Q protein and is part of the GPI-N-acetylglucosaminyltransferase complex that initiates GPI biosynthesis from phosphatidylinositol (PI) and N-acetylglucosamine (GlcNAc) on the cytoplasmic side of the endoplasmic reticulum (ER). Pathogenic variants in the PIGQ gene have been previously reported in 10 patients with congenital hypotonia, early-infantile epileptic encephalopathy, and premature death occurring in more than half cases. We detected a novel homozygous variant in PIGQ (NM_004204.5: c.1631dupA; p.Tyr544fs*79) by WES trio-analysis of a male patient with a neurodevelopmental disorder characterized by nonprogressive congenital ataxia, intellectual disability, generalized epilepsy, and cerebellar atrophy. Flow cytometry confirmed deficiency of several GPI-anchored proteins on leukocytes (CD14, FLAER). Clinical features of this case broaden the phenotypic spectrum of PIGQ-related GPI deficiency, outlining the importance of glycophosphatidylinositol (GPI) anchor pathway in the pathogenesis of cerebellar ataxia.

Two Italian Patients with ELOVL4-Related Neuro-Ichthyosis: Expanding the Genotypic and Phenotypic Spectrum and Ultrastructural Characterization

Elongation of Very Long Chain Fatty Acid-4 (ELOVL4) is a fatty acid elongase responsible for very long-chain fatty acid biosynthesis in the brain, retina, and skin. Heterozygous mutations in ELOVL4 gene cause Stargardt-like macular dystrophy and spinocerebellar ataxia type-34, while different homozygous mutations have been associated with ichthyosis, spastic quadriplegia, and mental retardation syndrome in three kindred. We report the first two Italian children affected with neuro-ichthyosis due to the previously undescribed ELOVL4 homozygous frameshift variant c.435dupT (p.Ile146TyrfsTer29), and compound heterozygous variants c.208C>T (p.Arg70Ter) and c.487T>C (p.Cys163Arg), respectively. Both patients were born with collodion membrane followed by development of diffuse mild hyperkeratosis and scaling, localized erythema, and palmoplantar keratoderma. One infant displayed mild facial dysmorphism. They suffered from failure to thrive, and severe gastro-esophageal reflux with pulmonary aspiration. The patients presented axial hypotonia, hypertonia of limbs, and absent head control with poor eye contact from infancy. Visual evoked potentials showed markedly increased latency and poor morphological definition, indicative of alteration of the retro-retinal visual pathways in both patients. Ultrastructural skin examination revealed abnormalities of lamellar bodies with altered release in the epidermal granular and horny layer intracellular spaces. Our findings contribute to expanding the phenotypic and genotypic features of ELOVL4-related neuro-ichthyosis.

Clinical phenotypes of infantile onset CACNA1A-related disorder

BACKGROUND

CACNA1A-related disorders present with persistent progressive and non-progressive cerebellar ataxia and paroxysmal events: epileptic seizures and non-epileptic attacks. These phenotypes overlap and co-exist in the majority of patients.

OBJECTIVE

To describe phenotypes in infantile onset CACNA1A-related disorder and to explore intra-familial variations and genotype-phenotype correlations.

MATERIAL AND METHODS

This study was a multicenter international collaboration. A retrospective chart review of CACNA1A patients was performed. Clinical, radiological, and genetic data were collected and analyzed in 47 patients with infantile-onset disorder.

RESULTS

Paroxysmal non-epileptic events (PNEE) were observed in 68% of infants, with paroxysmal tonic upward gaze (PTU) noticed in 47% of infants. Congenital cerebellar ataxia (CCA) was diagnosed in 51% of patients including four patients with developmental delay and only one neurological sign. PNEEs were found in 63% of patients at follow-up, with episodic ataxia (EA) in 40% of the sample. Cerebellar ataxia was found in 58% of the patients at follow-up. Four patients had epilepsy in infancy and nine in childhood. Seven infants had febrile convulsions, three of which developed epilepsy later; all three patients had CCA. Cognitive difficulties were demonstrated in 70% of the children. Cerebellar atrophy was found in only one infant but was depicted in 64% of MRIs after age two.

CONCLUSIONS

Nearly all of the infants had CCA, PNEE or both. Cognitive difficulties were frequent and appeared to be associated with CCA. Epilepsy was more frequent after age two. Febrile convulsions in association with CCA may indicate risk of epilepsy in later childhood. Brain MRI was normal in infancy. There were no genotype-phenotype correlations found.

A Recurrent Pathogenic Variant of INPP5K Underlies Autosomal Recessive Congenital Muscular Dystrophy With Cataracts and Intellectual Disability: Evidence for a Founder Effect in Southern Italy

Inositol polyphosphate-5-phosphatase K [INPP5K (MIM: 607875)] acts as a PIP₃ 5-phosphatase and regulates actin cytoskeleton, insulin, and cell migration. Biallelic pathogenic variants in INPP5K have recently been reported in patients affected by a form of muscular dystrophy with childhood onset. Affected patients have limb girdle muscle weakness, often associated with bilateral cataracts, short stature, and intellectual disability. Here we report four patients affected by INPP5K-related muscle dystrophy, who were apparently unrelated but originated from the same geographical area in South Italy. These patients manifest a recognizable phenotype characterized by early onset muscular dystrophy associated with short stature and intellectual disability. All affected subjects were homozygous or compound heterozygous for the c.67G > A (p.Val23Met) missense change and shared a common haplotype, indicating the occurrence of a founder effect.

Heterozygous KIF1A variants underlie a wide spectrum of neurodevelopmental and neurodegenerative disorders

BACKGROUND

Dominant and recessive variants in the KIF1A gene on chromosome 2q37.3 are associated with several phenotypes, although only three syndromes are currently listed in the OMIM classification: hereditary sensory and autonomic neuropathy type 2 and spastic paraplegia type 30, both recessively inherited, and mental retardation type 9 with dominant inheritance.

METHODS

In this retrospective multicentre study, we describe the clinical, neuroradiological and genetic features of 19 Caucasian patients (aged 3-65 years) harbouring heterozygous KIF1A variants, and extensively review the available literature to improve current classification of KIF1A-related disorders.

RESULTS

Patients were divided into two groups. Group 1 comprised patients with a complex phenotype with prominent pyramidal signs, variably associated in all but one case with additional features (ie, epilepsy, ataxia, peripheral neuropathy, optic nerve atrophy); conversely, patients in group 2 presented an early onset or congenital ataxic phenotype. Fourteen different heterozygous missense variants were detected by next-generation sequencing screening, including three novel variants, most falling within the kinesin motor domain.

CONCLUSION

The present study further enlarges the clinical and mutational spectrum of KIF1A-related disorders by describing a large series of patients with dominantly inherited KIF1A pathogenic variants ranging from pure to complex forms of hereditary spastic paraparesis/paraplegias (HSP) and ataxic phenotypes in a lower proportion of cases. A comprehensive review of the literature indicates that KIF1A screening should be implemented in HSP regardless of its mode of inheritance or presentations as well as in other complex neurodegenerative or neurodevelopmental disorders showing congenital or early onset ataxia.

Prestatus and status dystonicus in children and adolescents

AIM

To critically analyse the management of status dystonicus and prestatus dystonicus in children and adolescents, in order to examine clinical features, acute management, and risk of relapse in a paediatric cohort.

METHOD

Clinical, demographic, and therapeutic features were analysed according to disease severity. Risk of subsequent relapse was estimated through Kaplan-Meier curves.

RESULTS

Thirty-four patients (eight females, 26 males) experiencing 63 episodes of acute dystonia exacerbations at a tertiary referral Italian hospital were identified. Mean age at status dystonicus presentation was 9 years 11 months (11y at inclusion in the study). Onset of dystonia dated back to infancy in most cases. Fourteen patients experienced two or more episodes. Infections were the most common trigger (48%). Benzodiazepines were the most commonly used drugs for acute management. Stereotactic pallidotomy was performed in six cases during status dystonicus, and in two additional patients it was electively performed after medical management. The probability of survival free from status dystonicus relapses was 78% after 4 months and 61% after 27 months.

INTERPRETATION

Dystonia exacerbations are potentially life-threating emergencies, with a considerable risk of relapse. Nevertheless, no obvious factors for relapse risk stratification exist. Pallidotomy is a feasible option in medical refractory status dystonicus for patients with limited deep brain stimulation applicability, but the risk of recurrence is elevated.

WHAT THIS PAPER ADDS

Acute exacerbations may affect up to 10% of children with dystonia. Infections are the most common precipitant factor. In about 30% of the cases, intensive care unit admission is needed. Subsequent relapses are common, reaching 25% risk at 1 year. Pallidotomy can be considered in medical-refractory cases with no deep brain stimulation applicability.

TUBB Variants Underlying Different Phenotypes Result in Altered Vesicle Trafficking and Microtubule Dynamics

Tubulinopathies are rare neurological disorders caused by alterations in tubulin structure and function, giving rise to a wide range of brain abnormalities involving neuronal proliferation, migration, differentiation and axon guidance. TUBB is one of the ten β-tubulin encoding genes present in the human genome and is broadly expressed in the developing central nervous system and the skin. Mutations in TUBB are responsible for two distinct pathological conditions: the first is characterized by microcephaly and complex structural brain malformations and the second, also known as “circumferential skin creases Kunze type” (CSC-KT), is associated to neurological features, excess skin folding and growth retardation. We used a combination of immunocytochemical and cellular approaches to explore, on patients’ derived fibroblasts, the functional consequences of two TUBB variants: the novel mutation (p.N52S), associated with basal ganglia and cerebellar dysgenesis, and the previously reported variant (p.M73T), linked to microcephaly, corpus callosum agenesis and CSC-KT skin phenotype. Our results demonstrate that these variants impair microtubule (MT) function and dynamics. Most importantly, our studies show an altered epidermal growth factor (EGF) and transferrin (Tf) intracellular vesicle trafficking in both patients’ fibroblasts, suggesting a specific role of TUBB in MT-dependent vesicular transport.

Heterozygous missense variants of SPTBN2 are a frequent cause of congenital cerebellar ataxia

Heterozygous missense variants in the SPTBN2 gene, encoding the non-erythrocytic beta spectrin 2 subunit (beta-III spectrin), have been identified in autosomal dominant spinocerebellar ataxia type 5 (SCA5), a rare adult-onset neurodegenerative disorder characterized by progressive cerebellar ataxia, whereas homozygous loss of function variants in SPTBN2 have been associated with early onset cerebellar ataxia and global developmental delay (SCAR14). Recently, heterozygous SPTBN2 missense variants have been identified in a few patients with an early-onset ataxic phenotype. We report five patients with non-progressive congenital ataxia and psychomotor delay, 4/5 harboring novel heterozygous missense variants in SPTBN2 and one patient with compound heterozygous SPTBN2 variants. With an overall prevalence of 5% in our cohort of unrelated patients screened by targeted next-generation sequencing (NGS) for congenital or early-onset cerebellar ataxia, this study indicates that both dominant and recessive mutations of SPTBN2 together with CACNA1A and ITPR1, are a frequent cause of early-onset/congenital non-progressive ataxia and that their screening should be implemented in this subgroup of disorders.

SLC2A1 mutations are a rare cause of pediatric-onset hereditary spastic paraplegia

SLC2A1 mutations cause glucose transporter type 1 deficiency syndrome, whose phenotypic spectrum is a continuum, ranging from classic to variant phenotypes, the latter accounting for about 10% of cases. Very few SLC2A1-mutated patients with a spastic paraplegia phenotype have been reported so far, and they are associated with paroxysmal choreo-athetosis (i.e., DYT9). The authors describe two sporadic children with pure and complex hereditary spastic paraplegia (HSP) without paroxysmal non-epileptic movement disorders harboring heterozygous de novo SLC2A1 pathogenic variants. These patients have been identified by a targeted panel for HSP among 140 pediatric- and adult-onset unrelated cases with pure and complex HSP, thus indicating an overall prevalence of 1.4% of SLC2A1 mutations, which increases to 3% if only pediatric-onset patients are considered. The implications of these findings in the diagnostic work-up of HSP patients are discussed.

Could Rolandic spikes be a prognostic factor of the neurocognitive outcome of children with BECTS?

INTRODUCTION

Rolandic epilepsy, also known as benign childhood epilepsy with centrotemporal spikes (BECTS), is one of the most common epileptic syndromes in previously healthy children. Despite what was known about the benignity of this syndrome, there is always more evidence about the involvement of the cognitive functions with different deficits in several domains to be investigated.

AIM OF THE STUDY

The aim of our study was to describe prognostic electroencephalogram (EEG) pattern of an adverse cognitive development to recognize patients at higher risk of lasting cognitive deficits that could need antiepileptic drugs (AEDs) or an improved neurocognitive therapy. In addition, we wanted to investigate the existence of a possible linkage between the number of interictal epileptiform discharges (IEDs) in the EEG and the more pronounced cognitive deficits.

MATERIAL AND METHODS

We performed a case-control study on a cohort of 16 patients (10 male and 6 female) aged 4-14, diagnosed with BECTS who underwent EEG, magnetic resonance imaging (MRI), and neurocognitive assessment at the Pediatric Neurology Unit at the Umberto I Hospital, Sapienza University of Rome. Patients were divided into two groups according to the percentage of IEDs evaluated based on their sleep EEG: group A with less than 50% of the entire EEG invaded by discharges in more than 70% of the total number of EEG performed, so-called with low or intermediate activation. On the contrary, group B had a high activation, with more than 50% of the entire EEG invaded by discharges in the same percentage of the EEG performed. All children were assessed based on a protocol designed to study neuropsychological functions with specific tests chosen depending on age (Wechsler Intelligence Scale for Children IV: WISC IV; Wechsler Preschool and Primary Scale of Intelligence III: WPPSI III). Groups were compared for cognitive outcomes achieved by each patient through Student's t-test with a significance level of p<0.05 (two-tailed).

RESULTS

There is no statistically significant difference in the cognitive outcomes of these patients: Student's t-test showed a statistical significance (p) for each cognitive index always higher than 0.05, demonstrating that the intellectual quotient (IQ) and all other indexes analyzed (verbal comprehension index (VCI), perceptual reasoning index (PRI), working memory index (WMI), and processing speed index (PSI)) are not affected by the difference in EEG anomalies presented by our patients. Interestingly, all patients had an IQ equal to or greater than the Italian average (12 out of 16 patients showed an IQ>100), with selective drops, particularly significant in the WMI and also in the PSI.

CONCLUSIONS

Our results clearly demonstrate the importance of a proper evaluation of patients with this kind of epilepsy, without paying attention only to those with the greatest number of IEDs or seizures because all of them had a neurocognitive impairment, especially in memory. These data may be reinforced by a larger sample for an even more significant statistical value. These results also highlight the importance of a neurocognitive therapy for these children to treat for their specific needs.

ATP1A3-related epileptic encephalopathy responding to ketogenic diet

BACKGROUND

Alternating Hemiplegia of Childhood (AHC) is a rare neurological disease caused by mutations in ATP1A3 gene codifying for alpha3 subunit of Na⁺-K⁺ ATPase pump. Repeated and transient attacks of hemiplegia, usually affecting one side of the body or the other, or both sides of the body at once, are the core features of AHC. Monocular nystagmus, other abnormalities in ocular movements, dystonic posturing and epilepsy are commonly associated to AHC. However, the spectrum of ATP1A3 related diseases is still expanding and new phenotypes have been reported.

CASE REPORT

Here, we described a patient who developed a severe early onset drug-resistant epileptic encephalopathy and months later, he presented episodes of hemiplegic attacks and monocular nystagmus. Thus, AHC was hypothesized and a novel mutation in ATP1A3 gene was found. Interestingly, ketogenic diet (KD) was started and both epileptic seizures and classical AHC paroxysmal episodes stopped. Long-term follow-up shows a global improvement of neurological development.

CONCLUSIONS

Our case reinforces the role of KD as a novel therapeutic option for ATP1A3-related conditions. However, proper dedicated confirmatory trials on KD are necessary.

Novel homozygous GBA2 mutation in a patient with complicated spastic paraplegia

Hereditary spastic paraplegias (HSPs) are a heterogeneous group of neurological disorders characterized primarily by a pyramidal syndrome with lower limb spasticity, which can manifest as pure HSP or associated with a number of neurological or non-neurological signs (i.e., complicated HSPs). The clinical variability of HSPs is associated with a wide genetic heterogeneity, with more than eighty causative genes known. Recently, next generation sequencing (NGS) has allowed increasing genetic definition in such a heterogeneous group of disorders. We report on a 56- year-old man affected by sporadic complicated HSP consisting of a pyramidal syndrome, cerebellar ataxia, congenital cataract, pes cavus, axonal sensory-motor peripheral neuropathy and cognitive decline. Brain MRI showed cerebellar atrophy and thin corpus callosum. By NGS we found a novel homozygous biallelic c.452-1G > C mutation in the b-glucosidase 2 gene (GBA2), known to be causative for autosomal recessive hereditary spastic paraplegia type 46 (SPG46). The rarity of this inherited form besides reporting on a novel mutation, expands the genetic and clinical spectrum of SPG46 related HSP.

A mosaic pattern of INI1/SMARCB1 protein expression distinguishes Schwannomatosis and NF2-associated peripheral schwannomas from solitary peripheral schwannomas and NF2-associated vestibular schwannomas

BACKGROUND

The INI1/SMARCB1 gene protein product has been implicated in the direct pathogenesis of schwannomas from patients with one form of schwannomatosis [SWNTS1; MIM # 162091] showing a mosaic pattern of loss of protein expression by immunohistochemistry [93% in familial vs. 55% in sporadic cases].

AIM OF STUDY

To verify whether such INI1/SMARCB1 mosaic pattern could be extended to all schwannomas arising in the sporadic and familial schwannomatoses [i.e. to SMARCB1-related (SWNTS1) or LZTR1-related (SWNTS2) schwannomatosis or to SMARCB1/LZTR1-negative schwannomatosis] and whether it could be involved in classical NF2 or solitary peripheral schwannomas METHODS: We blindly analysed schwannoma samples obtained from a total of 22 patients including (a) 2 patients (2 males; aged 38 and 55 years) affected by non-familial SMARCB1-associated schwannomatosis (SWTNS1); (b) 1 patient (1 female; aged 33 years) affected by familial schwannomatosis (SWTNS1/ SMARCB1 germ line mutations); (c) 5 patients (3 males, 2 females; aged 33 to 35 years) affected by non-familial (sporadic) LZTR1-associated schwannomatosis (SWNTS2); (d) 3 patients (3 males; aged 35 to 47 years) affected by familial schwannomatosis (SWTNS2/ LZTR1 germ line mutations); (e) 2 patients (1 male, 1 female; aged 63 and 49 years, respectively) affected by non-familial schwannomatosis (SWTNS, negative for SMARCB1, LZTR1 and NF2 gene mutations); (f) 4 patients (3 males, 1 females; aged 15 to 24 years) affected by classical NF2 (NF2: harbouring NF2 germ line mutations; and (g) 5 patients (3 males, 2 females; aged 33 to 68 years) who had solitary schwannomas. [follow-up = 15-30 years; negative for constitutional/somatic mutation analysis for the SMARCB1, LZTR1 and NF2 genes] were (blindly) analyzed. The INI1/SMARCB1 immunostaining pattern was regarded as (1) diffuse positive nuclear staining [= retained expression] or (2) mosaic pattern [mixed positive/negative nuclei = loss of expression in a subset of tumour cells].

RESULTS

All solitary peripheral schwannomas and NF2-associated vestibular schwannomas showed diffuse nuclear INI1/SMARCB1 staining in 97-100% of neoplastic cells; schwannomas obtained from all cases of non-familial and familial schwannomatosis and NF2-associated non-vestibular schwannomas showed a mosaic pattern ranging from 10 to 70% of INI1/SMARCB1-positive expression. We did not record a complete lack of nuclear staining.

CONCLUSIONS

The present data suggests that (a) mosaic loss of immunohistochemical INI1/SMARCB1 expression, despite the interlesional variability, is a reliable marker of schwannomatosis regardless of the involved gene and it might help in the differential diagnosis of schwannomatosis vs. solitary schwannomas and (b) INI1/SMARCB1 expression is not useful in the differential with mosaic NF2, since NF2-associated peripheral schwannomas show the same immunohistochemical pattern.

Beverage consumption and paediatric NAFLD

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in children and adolescents, due to the increased worldwide incidence of obesity among children. It is now clear enough that of diet high in carbohydrates and simple sugars are associated with hepatic steatosis and non-alcoholic steatohepatitis (NASH). Several studies have shown that an increased consumption of simple sugars is also positively associated with overweight and obesity, and related co-morbidities, such as type 2 diabetes, metabolic syndrome and NAFLD. It is difficult to define the role of the various components of soft drinks and energy drinks in the pathogenesis of NAFLD and its progression in NASH, but the major role is played by high calorie and high sugar consumption, mainly fructose. In addition, other components of these beverages (e.g. xanthine) seem to have an important role in the pathogenesis of metabolic disorders, crucial pathways involved in NAFLD/NASH. The drastic reduction in the consumption of energy drinks and soft drinks is an appropriate intervention for the prevention of obesity and NAFLD in young people.

Effectiveness and tolerability of perampanel in children and adolescents with refractory epilepsies-An Italian observational multicenter study

PURPOSE

To evaluate the efficacy and tolerability of Perampanel (PER) in children and adolescents with refractory epilepsies in daily clinical practice conditions.

PATIENTS AND METHODS

This Italian multicenter retrospective observational study was performed in 16 paediatric epilepsy centres. Inclusion criteria were: (i) ≤18 years of age, (ii) history of refractory epilepsy, (iii) a follow-up ≥5 months of PER add-on therapy. Exclusion criteria were: (i) a diagnosis of primary idiopathic generalized epilepsy, (ii) variation of concomitant AEDs during the previous 4 weeks. Response was defined as a ≥50% reduction in monthly seizure frequency compared with the baseline.

RESULTS

62 patients suffering from various refractory epilepsies were included in this study: 53% were males, the mean age was 14.2 years (range 6-18 years), 8 patients aged <12 years. Mean age at epilepsy onset was 3.4 years and the mean duration of epilepsy was 10.8 years (range 1-16), which ranged from 2 seizures per-month up to several seizures per-day (mean number=96.5). Symptomatic focal epilepsy was reported in 62.9% of cases. Mean number of AEDs used in the past was 7.1; mean number of concomitant AEDs was 2.48, with carbamazepine used in 43.5% of patients. Mean PER daily dose was 7.1mg (2-12mg). After an average of 6.6 months of follow-up (5-13 months), the retention rate was 77.4% (48/62). The response rate was 50%; 16% of patients achieved ≥75% seizure frequency reduction and 5% became completely seizure free. Seizure aggravation was observed in 9.7% of patients. Adverse events were reported in 19 patients (30.6%) and led to PER discontinuation in 4 patients (6.5%). The most common adverse events were behaviour disturbance (irritability and aggressiveness), dizziness, sedation and fatigue.

CONCLUSION

PER was found to be a safe and effective treatment when used as adjunctive therapy in paediatric patients with uncontrolled epilepsy.

Stroke and migraine is there a possible comorbidity?

The association between migraine and stroke is still a dilemma for neurologists. Migraine is associated with an increased stroke risk and it is considered an independent risk factor for ischaemic stroke in a particular subgroup of patients. The pathogenesis is still unknown even if several studies report some common biochemical mechanisms between these two diseases. A classification of migraine-related stroke that encompasses the full spectrum of the possible relationship between migraine and stroke includes three main entities: coexisting stroke and migraine, stroke with clinical features of migraine, and migraine-induced stroke. The concept of migraine-induced stroke is well represented by migrainous infarction and it is described in the revised classification of the International Headache Society (IHS), representing the strongest demonstration of the relationship between ischaemic stroke and migraine. A very interesting common condition in stroke and migraine is patent foramen ovale (PFO) which could play a pathogenetic role in both disorders. The neuroradiological evidence of subclinical lesions most typical in the white matter and in the posterior artery territories in patients with migraine, opens a new field of research. In conclusion the association between migraine and stroke remains an open question. Solving the above mentioned issues is fundamental to understand the epidemiologic, pathogenetic and clinical aspects of migraine-related stroke.

The possible use of the L-type calcium channel antagonist verapamil in drug-resistant epilepsy

Multidrug transporters (MDTs) are likely to play a role in the pathogenesis of drug resistance in epilepsy, acting at the level of the blood-brain barrier by returning antiepileptic drugs to the blood vessels and lowering brain penetration and concentration (e.g. the so-called multidrug transporter hypothesis). In the last ten years experimental studies on both animal models and human brain tissues have highlighted a potential role of the P-glycoprotein-one of the multidrug transporters of the blood-brain barrier-in the pathophysiology of drug-resistant epilepsies. At the same time, verapamil has been administered to patients with drug-resistant epilepsy (e.g., Dravet syndrome, Lennox-Gastaut syndrome, focal epilepsies) or status epilepticus with promising results. In this drug profile paper the authors review current knowledge and main published studies regarding the role of the L-type calcium channel antagonist verapamil in drug-resistant epilepsy.

Severe early onset ethylmalonic encephalopathy with West syndrome

Ethylmalonic encephalopathy (EE) is a rare autosomal recessive disorder characterized by early onset encephalopathy, chronic diarrhoea, petechiae, orthostatic acrocyanosis and defective cytochrome c oxidase (COX) in muscle and brain. High levels of lactic, ethylmalonic and methylsuccinic acids are detected in body fluids. EE is caused by mutations in ETHE1 gene, a mitochondrial sulfur dioxygenase. Neurologic signs and symptoms include progressively delayed development, hypotonia, seizures, and abnormal movements. We report on the clinical, electroencephalographic and MRI findings of a baby with a severe early onset encephalopathy associated with novel ETHE1 gene mutation. This is the first case described in literature with an early pure epileptic onset, presenting with West syndrome.

Neurological features of 14q24-q32 interstitial deletion: report of a new case

Background

Interstitial deletions of the long arm of chromosome 14 involving the 14q24-q32 region have been reported in less than 20 patients. Previous studies mainly attempted to delineate recognizable facial dysmorphisms; conversely, descriptions on neurological features are limited to the presence of cognitive and motor delay, but no better characterization exists.

Case presentation

In this paper we report on a patient with a de novo interstitial deletion of 5.5 Mb at 14q24.3-q31.1. The deletion encompasses 84 genes, including fourteen Mendelian genes. He presented with dysmorphic face, developmental delay, paroxysmal non-epileptic events and, subsequently, epilepsy.

Conclusions

The clinical and molecular evaluation of this patient and the review of the literature expand the phenotype of 14q23-q32 deletion syndrome to include paroxysmal non-epileptic events and infantile-onset focal seizures.