Intravenous thrombolysis + endovascular thrombectomy versus thrombolysis alone in large vessel occlusion mild stroke: a propensity score matched analysis.

BACKGROUND AND PURPOSE: The best reperfusion treatment for patients with mild acute ischaemic stroke harbouring proximal anterior circulation large vessel occlusion (LVO) is unknown. The aim was to compare the safety and efficacy of intravenous thrombolysis (IVT) plus endovascular thrombectomy (EVT) versus IVT alone in LVO patients with mild symptoms. METHODS: From the Safe Implementation of Treatment in Stroke-International Stroke Thrombolysis and Thrombectomy Register (SITS-ISTR), were included: (i) consecutive acute ischaemic stroke patients, (ii) treated within 4.5 h from symptoms onset, (iii) baseline National Institutes of Health Stroke Scale (NIHSS) score ≤5 and (iv) intracranial internal carotid artery [ICA], M1 or T occlusion [defined as occlusion of ICA terminal bifurcation]. After propensity score matching, 3-month functional outcomes (modified Rankin Scale [mRS] 0-1 and 0-2) and safety outcomes (symptomatic intracerebral haemorrhage and death) were compared (via univariable and multivariable logistic [and ordinal] regression analyses) in patients treated with IVT + EVT versus IVT alone. RESULTS: In all, 1037 patients were included. After propensity score matching (n = 312 per group), IVT + EVT was independently associated with poor functional outcomes (adjusted odds ratio [aOR] 0.46 for mRS 0-1, 95% confidence interval [CI] 0.30-0.72, p = 0.001; aOR 0.52 for mRS 0-2, 95% CI 0.32-0.84, p = 0.007; aOR 1.61 for 1-point shift in mRS score, 95% CI 1.12-2.32, p = 0.011), with no significant differences in safety outcomes compared to IVT alone, despite numerically higher rates of symptomatic intracerebral haemorrhage (3.3% vs. 1.1%; p = 0.082), a higher rate of any haemorrhagic transformation (17.6% vs. 7.3%; p < 0.001) and subarachnoid haemorrhage (7.9% vs. 1.5%; p = 0.002) in the IVT + EVT group. DISCUSSION: In anterior circulation LVO patients presenting with NIHSS score ≤5, IVT + EVT (vs. IVT alone) was associated with poorer 3-month functional outcome. Randomized controlled trials are needed to elucidate the best treatments in mild LVO patients.

Advancing Stroke Research on Cerebral Thrombi with Omic Technologies.

Cerebrovascular diseases represent a leading cause of disability, morbidity, and death worldwide. In the last decade, the advances in endovascular procedures have not only improved acute ischemic stroke care but also conceded a thorough analysis of patients' thrombi. Although early anatomopathological and immunohistochemical analyses have provided valuable insights into thrombus composition and its correlation with radiological features, response to reperfusion therapies, and stroke etiology, these results have been inconclusive so far. Recent studies applied single- or multi-omic approaches-such as proteomics, metabolomics, transcriptomics, or a combination of these-to investigate clot composition and stroke mechanisms, showing high predictive power. Particularly, one pilot studies showed that combined deep phenotyping of stroke thrombi may be superior to classic clinical predictors in defining stroke mechanisms. Small sample sizes, varying methodologies, and lack of adjustments for potential confounders still represent roadblocks to generalizing these findings. However, these techniques hold the potential to better investigate stroke-related thrombogenesis and select secondary prevention strategies, and to prompt the discovery of novel biomarkers and therapeutic targets. In this review, we summarize the most recent findings, overview current strengths and limitations, and present future perspectives in the field.

Loss of the nucleoporin Aladin in central nervous system and fibroblasts of Allgrove Syndrome.

Allgrove syndrome (AS) is a rare disease with broad neurological involvement. Neurodegeneration can affect spinal motor neurons, Purkinje cells, striatal neurons and the autonomic system. The mechanisms that lead to neuronal loss are still unclear. Recessive mutations in the AAAS gene affect the encoded protein Aladin, which would normally localize to the cytoplasmic face of the nuclear membrane as part of the nuclear pore complex (NPC). While the NPC is known to be a key factor for nucleocytoplasmic transport, the precise role of Aladin has not been elucidated yet. Here, we explored the consequences of the homozygous AAAS mutation c.464G>A (p.R155H) in central nervous system tissues and fibroblasts of a novel AS patient presenting motor neuron disease, cerebellar ataxia and autonomic dysfunction. Neuropathological analyses showed severe loss of motor neurons and Purkinje cells, with significant reduction in the perinuclear expression of Aladin. A reduced amount of protein was detected in the nuclear membrane fraction of the patient's brain. RNA analysis revealed a significant reduction of the transcript AAAS-1, while the AAAS-2 transcript was upregulated in fibroblasts. To our knowledge, this is the first study to demonstrate the effects of AAAS mutations in the human central nervous system.

Consumption of complement in a 26-year-old woman with severe thrombotic thrombocytopenia after ChAdOx1 nCov-19 vaccination.

Extremely rare reactions characterized by thrombosis and thrombocytopenia have been described in subjects that received ChAdOx1 nCoV-19 vaccination 5-16 days earlier. Although patients with vaccine-induced thrombotic thrombocytopenia (VITT) have high levels of antibodies to platelet factor 4 (PF4)-polyanion complexes, the exact mechanism of the development of thrombosis is still unknown. Here we reported serum studies as well as proteomics and genomics analyses demonstrating a massive complement activation potentially linked to the presence of anti-PF4 antibodies in a patient with severe VITT. At admission, complement activity of the classical and lectin pathways were absent (0% for both) with normal levels of the alternative pathway (73%) in association with elevated levels of the complement activation marker sC5b-9 (630 ng/mL [n.v. 139-462 ng/mL]) and anti-PF4 IgG (1.918 OD [n.v. 0.136-0.300 OD]). The immunoblotting analysis of C2 showed the complete disappearance of its normal band at 110 kDa. Intravenous immunoglobulin treatment allowed to recover complement activity of the classical pathway (91%) and lectin pathway (115%), to reduce levels of sC5b-9 (135 ng/mL) and anti-PF4 IgG (0.681 OD) and to normalize the C2 pattern at immunoblotting. Proteomics and genomics analyses in addition to serum studies showed that the absence of complement activity during VITT was not linked to alterations of the C2 gene but rather to a strong complement activation leading to C2 consumption. Our data in a single patient suggest monitoring complement parameters in other VITT patients considering also the possibility to target complement activation with specific drugs.

Safety and efficacy of rt-PA treatment for acute stroke in pseudoxanthoma elasticum: the first report.

Pseudoxanthoma elasticum is a rare cause for ischaemic stroke. Little is known about acute and secondary prevention strategies in these subjects given the increased risk of gastrointestinal and urinary bleedings. Here we present the case of a 62 years old man affected by pseudoxanthoma elasticum who presented with acute ischaemic stroke and was successfully treated with intravenous thrombolysis. Neurological signs improved after intravenous thrombolysis without bleeding complication. To our knowledge, this is the first case of pseudoxanthoma elasticum-related stroke undergoing intravenous thrombolysis.

Targeting the Autonomic Nervous System for Risk Stratification, Outcome Prediction and Neuromodulation in Ischemic Stroke.

Ischemic stroke is a worldwide major cause of mortality and disability and has high costs in terms of health-related quality of life and expectancy as well as of social healthcare resources. In recent years, starting from the bidirectional relationship between autonomic nervous system (ANS) dysfunction and acute ischemic stroke (AIS), researchers have identified prognostic factors for risk stratification, prognosis of mid-term outcomes and response to recanalization therapy. In particular, the evaluation of the ANS function through the analysis of heart rate variability (HRV) appears to be a promising non-invasive and reliable tool for the management of patients with AIS. Furthermore, preclinical molecular studies on the pathophysiological mechanisms underlying the onset and progression of stroke damage have shown an extensive overlap with the activity of the vagus nerve. Evidence from the application of vagus nerve stimulation (VNS) on animal models of AIS and on patients with chronic ischemic stroke has highlighted the surprising therapeutic possibilities of neuromodulation. Preclinical molecular studies highlighted that the neuroprotective action of VNS results from anti-inflammatory, antioxidant and antiapoptotic mechanisms mediated by α7 nicotinic acetylcholine receptor. Given the proven safety of non-invasive VNS in the subacute phase, the ease of its use and its possible beneficial effect in hemorrhagic stroke as well, human studies with transcutaneous VNS should be less challenging than protocols that involve invasive VNS and could be the proof of concept that neuromodulation represents the very first therapeutic approach in the ultra-early management of stroke.

Hereditary hemorrhagic telangiectasia associated with cortical development malformation due to a start loss mutation in ENG.

BACKGROUND: Hereditary hemorrhagic telangiectasia (HHT), also known as Rendu-Osler-Weber syndrome, is a rare disorder characterized by recurrent epistaxis, telangiectasias and systemic arteriovenous malformations (AVMs). HHT is associated with mutations in genes encoding for proteins involved in endothelial homeostasis such as ENG (endoglin) and ACVRL1 (activin receptor-like kinase-1). CASE PRESENTATION: Here we describe a 22-year-old male presenting with a transient episode of slurred speech and left arm paresis. Brain MRI displayed polymicrogyria. A right-to-left shunt in absence of an atrial septum defect was noted. Chest CT revealed multiple pulmonary AVMs, likely causing paradoxical embolism manifesting as a transient ischemic attack. The heterozygous ENG variant, c.3G > A (p.Met1lle), was detected in the patient. This variant was also found in patient's mother and in his younger brother who displayed cortical dysplasia type 2. CONCLUSIONS: The detection of cortical development malformations in multiple subjects from the same pedigree may expand the phenotypic features of ENG-related HHT patients. We suggest considering HHT in young patients presenting with acute cerebral ischemic events of unknown origin.

RNASEH1 Mutations Impair mtDNA Replication and Cause Adult-Onset Mitochondrial Encephalomyopathy.

Chronic progressive external ophthalmoplegia (CPEO) is common in mitochondrial disorders and is frequently associated with multiple mtDNA deletions. The onset is typically in adulthood, and affected subjects can also present with general muscle weakness. The underlying genetic defects comprise autosomal-dominant or recessive mutations in several nuclear genes, most of which play a role in mtDNA replication. Next-generation sequencing led to the identification of compound-heterozygous RNASEH1 mutations in two singleton subjects and a homozygous mutation in four siblings. RNASEH1, encoding ribonuclease H1 (RNase H1), is an endonuclease that is present in both the nucleus and mitochondria and digests the RNA component of RNA-DNA hybrids. Unlike mitochondria, the nucleus harbors a second ribonuclease (RNase H2). All affected individuals first presented with CPEO and exercise intolerance in their twenties, and these were followed by muscle weakness, dysphagia, and spino-cerebellar signs with impaired gait coordination, dysmetria, and dysarthria. Ragged-red and cytochrome c oxidase (COX)-negative fibers, together with impaired activity of various mitochondrial respiratory chain complexes, were observed in muscle biopsies of affected subjects. Western blot analysis showed the virtual absence of RNase H1 in total lysate from mutant fibroblasts. By an in vitro assay, we demonstrated that altered RNase H1 has a reduced capability to remove the RNA from RNA-DNA hybrids, confirming their pathogenic role. Given that an increasing amount of evidence indicates the presence of RNA primers during mtDNA replication, this result might also explain the accumulation of mtDNA deletions and underscores the importance of RNase H1 for mtDNA maintenance.

Purkinje cell COX deficiency and mtDNA depletion in an animal model of spinocerebellar ataxia type 1.

Spinocerebellar ataxias (SCAs) are a genetically heterogeneous group of cerebellar degenerative disorders, characterized by progressive gait unsteadiness, hand incoordination, and dysarthria. Ataxia type 1 (SCA1) is caused by the expansion of a CAG trinucleotide repeat in the SCA1 gene resulting in the atypical extension of a polyglutamine (polyQ) tract within the ataxin-1 protein. Our main objective was to investigate the mitochondrial oxidative metabolism in the cerebellum of transgenic SCA1 mice. SCA1 transgenic mice develop clinical features in the early life stages (around 5 weeks of age) presenting pathological cerebellar signs with concomitant progressive Purkinje neuron atrophy and relatively little cell loss; this evidence suggests that the SCA1 phenotype is not the result of cell death per se, but a possible effect of cellular dysfunction that occurs before neuronal demise. We studied the mitochondrial oxidative metabolism in cerebellar cells from both homozygous and heterozygous transgenic SCA1 mice, aged 2 and 6 months. Histochemical examination showed a cytochrome-c-oxidase (COX) deficiency in the Purkinje cells (PCs) of both heterozygous and homozygous mice, the oxidative defect being more prominent in older mice, in which the percentage of COX-deficient PC was up to 30%. Using a laser-microdissector, we evaluated the mitochondrial DNA (mtDNA) content on selectively isolated COX-competent and COX-deficient PC by quantitative Polymerase Chain Reaction and we found mtDNA depletion in those with oxidative dysfunction. In conclusion, the selective oxidative metabolism defect observed in neuronal PC expressing mutant ataxin occurs as early as 8 weeks of age thus representing an early step in the PC degeneration process in SCA1 disease.

Defective autophagy in spastizin mutated patients with hereditary spastic paraparesis type 15.

Hereditary spastic paraparesis type 15 is a recessive complicated form of the disease clinically characterized by slowly progressive spastic paraparesis and mental deterioration with onset between the first and second decade of life. Thinning of corpus callosum is the neuroradiological distinctive sign frequently associated with white matter abnormalities. The causative gene, ZFYVE26, encodes a large protein of 2539 amino acid residues, termed spastizin, containing three recognizable domains: a zinc finger, a leucine zipper and a FYVE domain. Spastizin protein has a diffuse cytoplasmic distribution and co-localizes partially with early endosomes, the endoplasmic reticulum, microtubules and vesicles involved in protein trafficking. In addition, spastizin localizes to the mid-body during the final step of mitosis and contributes to successful cytokinesis. Spastizin interacts with Beclin 1, a protein required for cytokinesis and autophagy, which is the major lysosome-mediated degradation process in the cell. In view of the Beclin 1-spastizin interaction, we investigated the possible role of spastizin in autophagy. We carried out this analysis by using lymphoblast and fibroblast cells derived from four different spastizin mutated patients (p.I508N, p.L243P, p.R1209fsX, p.S1312X) and from control subjects. Of note, the truncating p.R1209fsX and p.S1312X mutations lead to loss of spastizin protein. The results obtained indicate that spastizin interacts with the autophagy related Beclin 1-UVRAG-Rubicon multiprotein complex and is required for autophagosome maturation. In cells lacking spastizin or with mutated forms of the protein, spastizin interaction with Beclin 1 is lost although the formation of the Beclin 1-UVRAG-Rubicon complex can still be observed. However, in these cells we demonstrate an impairment of autophagosome maturation and an accumulation of immature autophagosomes. Autophagy defects with autophagosome accumulation can be observed also in neuronal cells upon spastizin silencing. These results indicate that autophagy is a central process in the pathogenesis of complicated forms of hereditary spastic paraparesis with thin corpus callosum.

Nitric oxide donor and non steroidal anti inflammatory drugs as a therapy for muscular dystrophies: evidence from a safety study with pilot efficacy measures in adult dystrophic patients.

This open-label, single centre pilot study was designed to evaluate safety and tolerability of the combination of the drugs isosorbide dinitrate, a nitric oxide donor, and ibuprofen, a non steroid anti-inflammatory drug, in a cohort of adult dystrophic patients (Duchenne, Becker and Limb-Girdle Muscular Dystrophy). Seventy-one patients were recruited: 35, treated with the drug combination for 12 months, and 36 untreated. Safety and adverse events were assessed by reported signs and symptoms, physical examinations, blood tests, cardiac and respiratory function tests. Exploratory outcomes measure, such as the motor function measure scale, were also applied. Good safety and tolerability profiles of the long-term co-administration of the drugs were demonstrated. Few and transient side effects (i.e. headache and low blood pressure) were reported. Additionally, exploratory outcomes measures were feasible in all the disease population studied and evidenced a trend towards amelioration that reached statistical significance in one dimension of the MFM scale. Systemic administration of ibuprofen and isosorbide dinitrate provides an adequate safety margin for clinical studies aimed at assessing efficacy.

New Insights into Cerebral Vessel Disease Landscapes at Single-Cell Resolution: Pathogenetic and Therapeutic Perspectives.

Cerebrovascular diseases are a leading cause of death and disability globally. The development of new therapeutic targets for cerebrovascular diseases (e.g., ischemic, and hemorrhagic stroke, vascular dementia) is limited by a lack of knowledge of the cellular and molecular biology of health and disease conditions and the factors that cause injury to cerebrovascular structures. Here, we describe the role of advances in omics technology, particularly RNA sequencing, in studying high-dimensional, multifaceted profiles of thousands of individual blood and vessel cells at single-cell resolution. This analysis enables the dissection of the heterogeneity of diseased cerebral vessels and their atherosclerotic plaques, including the microenvironment, cell evolutionary trajectory, and immune response pathway. In animal models, RNA sequencing permits the tracking of individual cells (including immunological, endothelial, and vascular smooth muscle cells) that compose atherosclerotic plaques and their alteration under experimental settings such as phenotypic transition. We describe how single-cell RNA transcriptomics in humans allows mapping to the molecular and cellular levels of atherosclerotic plaques in cerebral arteries, tracking individual lymphocytes and macrophages, and how these data can aid in identifying novel immune mechanisms that could be exploited as therapeutic targets for cerebrovascular diseases. Single-cell multi-omics approaches will likely provide the unprecedented resolution and depth of data needed to generate clinically relevant cellular and molecular signatures for the precise treatment of cerebrovascular diseases.

Sodium Levels Predict Disability at Discharge in Guillain-Barré Syndrome: A Retrospective Cohort Study.

Guillain-Barré syndrome (GBS) is an inflammatory polyradiculopathy with potentially severe complications. Clinical tools for risk stratification have been developed, but no definitive prognostic biomarker has been reported. Hyponatremia is frequent in GBS patients, but the impact of serum sodium levels on clinical outcomes is still ill-defined. In this retrospective cohort study, we included all adult patients diagnosed with GBS spectrum disorders at our center from January 2010 to July 2020. Disability at discharge was assessed with the GBS Disability Score (GDS), and all clinical and laboratory data was retrieved from medical charts. Thirty (58.8%) of the 51 subjects included in the study were discharged with severe residual disability (GDS ≥ 3). After accounting for relevant confounders, the odds of experiencing severe disability decreased by 27% (p = 0.027) for each unitary increase in serum sodium concentration. Thirteen (25.5%) patients were diagnosed with mild to moderate hyponatremia; the use of intravenous immune globulin (IVIG) independently increased the odds of developing hyponatremia. In conclusion, we found a significant, independent association between baseline serum sodium levels and severe disability at discharge in GBS patients. In our cohort, hyponatremia was more frequently observed after treatment with IVIG, suggesting dilutional pseudohyponatremia as a probable cause.

Spinal direct current stimulation (tsDCS) in hereditary spastic paraplegias (HSP): A sham-controlled crossover study.

Objective: Hereditary spastic paraplegia (HSP) represents a heterogeneous group of neurodegenerative diseases characterized by progressive spasticity and lower limb weakness. We assessed the effects of transcutaneous spinal direct current stimulation (tsDCS) in HSP.Design: A double-blind, randomized, crossover and sham-controlled study.Setting: Fondazione IRCCS Cà Granda, Ospedale Maggiore Policlinico, Milan.Participants: eleven patients with HSP (six men, mean age ± SD: 37.3 ± 8.1 years), eight affected by spastin/SPG4,1 by atlastin1/SPG3a, 1 by paraplegin/SPG7 and 1 by ZFYVE26/SPG15.Interventions: tsDCS (anodal or sham, 2.0 mA, 20', five days) delivered over the thoracic spinal cord (T10-T12).Outcome measures: Motor-evoked potentials (MEPs), the H-reflex (Hr), F-waves, the Ashworth scale for clinical spasticity, the Five Minutes Walking test and the Spastic Paraplegia Rating Scale (SPRS) were assessed. Patients were evaluated before tsDCS (T0), at the end of the stimulation (T1), after one week (T2), one month (T3) and two months (T4).Results: The score of the Ashworth scale improved in the anodal compared with sham group, up to two months following the end of stimulation (T1, P = .0137; T4, P = .0244), whereas the Five Minutes Walking test and SPRS did not differ between the two groups. Among neurophysiological measures, both anodal and sham tsDCS left Hr, F-waves and MEPs unchanged over time.Conclusions: Anodal tsDCS significantly decreases spasticity and might be a complementary strategy for the treatment of spasticity in HSP.

Clinical features and disease course of patients with acute ischaemic stroke just before the Italian index case: Was COVID-19 already there?

Since the end of February 2020, Italy has suffered one of the most severe outbreaks of coronavirus disease 2019 (COVID-19). However, what happened just before the Italian index case has not yet been investigated. To answer this question, we evaluated the potential impact of COVID-19 on the clinical features of a cohort of neurological inpatients admitted right before the Italian index case, as compared to the same period of the previous year. Demographic, clinical, treatment and laboratory data were extracted from medical records. The data collected included all inpatients who had been admitted to the Neurology and Stroke Units of the Ospedale Maggiore Policlinico, Milan, Italy, from December 15, 2018 to February 20, 2019 and from December 15, 2019 to February 20, 2020. Of the 248 patients, 97 subjects (39.1%) were admitted for an acute cerebrovascular event: 46 in the 2018/2019 period (mean [SD] age, 72.3 [15.6] years; 22 men [47.8%]), and 51 in the 2019/2020 interval (mean [SD] age, 72.8 [12.4] years; 24 men [47.1%]). The number of cryptogenic strokes has increased during the 2019-2020 year, as compared to the previous year (30 [58.8%] vs. 18 [39.1%], p = 0.05). These patients had a longer hospitalization (mean [SD] day, 15.7 [10.5] days vs. mean [SD] day, 11.7 [7.2] days, p = 0.03) and more frequent cerebrovascular complications (9 [30.0%] vs. 2 [11.1%]), but presented a lower incidence of cardiocerebral risk factors (18 [60.0%] vs. 14 [77.8%]). Right before the Italian index case, an increase in cryptogenic strokes has occurred, possibly due to the concomitant COVID-19.

Characterization of two novel SETX mutations in AOA2 patients reveals aspects of the pathophysiological role of senataxin.

Ataxia with oculomotor apraxia (AOA) type 2 (AOA2 MIM 606002) is a recessive subtype of AOA characterized by cerebellar atrophy, oculomotor apraxia, early loss of reflexes, and peripheral neuropathy. Various mutations either in homozygous or compound heterozygous condition were so far identified in the associated gene SETX (MIM 608465). SETX encodes a large protein called senataxin with a DNA-RNA helicase domain and a putative N-terminus protein interaction domain. Here, we report the identification of two novel homozygous mutations in SETX gene, c.340_342delCTT (p.L114Del) and c.1669C > T (p.R557X), in two AOA2 families. The characterization of the mutant lymphoblastoid cell lines for sensitivity to oxidative DNA-damaging agents indicates that the p.L114Del deletion confers an increased sensitivity to H2O2, camptothecin, and mitomycin C, previously found to induce death in lymphoblasts harbouring other SETX mutations; the cells carrying the nonsense mutation display instead values within the normal range. Further analysis of a neuronal cell model SKNBE, transfected with the mutant senataxin proteins, reveals increased sensitivity also to staurosporine and excitotoxicity associated with the p.L114Del mutant only. We also demonstrate that the sensitizing effect of p.L114Del on apoptosis can be reversed by senataxin silencing. The ability of a single amino acid deletion to sensitize cells to death by different agents, compared to the lack of effect of a whole protein deletion, seems to exclude a protective role played by the native protein while suggesting that a specific mutation confers to the protein the ability to enhance the toxic effect of various cell damaging agents.

A wide spectrum of clinical, neurophysiological and neuroradiological abnormalities in a family with a novel CACNA1A mutation.

BACKGROUND: Mutations in the calcium channel voltage dependent P/Q-type alpha-1A subunit (CACNA1A) can cause different neurological disorders which share a wide range of symptoms, including episodic ataxia type 2 (EA2), familial hemiplegic migraine (FHM1) and progressive spinocerebellar ataxia (SCA6). OBJECTIVE: To describe a three generations family in which a spectrum of different phenotypes, ranging from SCA6 (proband), to EA2 (proband's mother) to FHM1 (proband's mother and proband's aunt) was found. All of the family members carried a novel CACNA1A missense mutation. PATIENTS AND METHODS: A clinical, molecular, neuroradiological and neurophysiological study was carried out in all subjects. RESULTS: A single heterozygous base change in exon 9, c1213G-->A, leading to the amino acid substitution pAla405Thr was found to segregate within the family. Brain MRI showed cerebellar and cerebral atrophy signs in all but one mutation carriers. Neurophysiological findings (electroencephalography and evoked potentials) confirmed possible cerebral cortex and white matter involvement regardless of the clinical symptoms displayed. CONCLUSIONS: This novel CACNA1A mutation adds to the number of mutations associated with a heterogeneous clinical picture in family members. This mutation might affect the interaction between the intracellular loops and the beta subunit, leading to a relatively rapid cell death. In order to explain the wide phenotypic variability observed in this family, it is hypothesised that additional genetic and environmental (hormonal) factors play a role in the pathophysiology of the disease.

Dystonia-ataxia syndrome with permanent torsional nystagmus caused by ECHS1 deficiency.

Biallelic mutations in ECHS1, encoding the mitochondrial enoyl-CoA hydratase, have been associated with mitochondrial encephalopathies with basal ganglia involvement. Here, we describe a novel clinical presentation consisting of dystonia-ataxia syndrome with hearing loss and a peculiar torsional nystagmus observed in two adult siblings. The presence of a 0.9-ppm peak at MR spectroscopy analysis suggested the accumulation of branched-chain amino acids. Exome sequencing in index probands identified two ECHS1 mutations, one of which was novel (p.V82L). ECHS1 protein levels and residual activities were reduced in patients' fibroblasts. This paper expands the phenotypic spectrum observed in patients with impaired valine catabolism.