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The inherited neuropathies are a common and heterogeneous group of slowly progressive disorders affecting motor, sensory, and autonomic nerves. These hereditary conditions can be confined to the peripheral nervous system, termed the primary hereditary neuropathies, or can occur as part of a multisystem disease. Identification of systemic involvement is necessary to distinguish the primary and secondary hereditary neuropathies to prevent the misdiagnosis of potentially treatable entities. Recent genetic and technological advances have dramatically improved our understanding of the underlying pathophysiology of these inherited neuropathies and hence provide the correct milieu for the future development of disease-modifying therapies. This review provides clinical, neurophysiological, genetic, pathophysiological, and treatment insights into the primary inherited neuropathies, and those associated with multisystem diseases, including porphyria and mitochondrial disorders.

The notion that a group’s judgement may be superior to that of the individual continues to promote discussion.1 A study in Practical Neurology investigated the collective ‘wisdom of neurologists’ by analysing the distribution of 110 estimates of the master of ceremonies and presidential combined speech duration at the 2013 annual dinner of the Association of British Neurologists (ABN).2 That study emphasised a respect for cognitive divergence, whereby the inclusion of apparently anomalous estimates of the mean produced a more accurate prediction of the result (24 min and 30 s). We conducted a similar experiment …

Bortezomib-induced peripheral neuropathy (BIPN) is a common toxicity associated with the treatment of multiple myeloma (MM), typically requiring dose reduction, delay, or cessation of treatment protocol. This systematic review aimed to investigate risk factors, trends, and variability associated with the development of BIPN. Searches were undertaken using Medline, PubMed, Cochrane Central Register of Controlled Trials, Embase, Scopus, and Web of Science. Additional studies were identified by investigating authors' bibliographic references cited by original and review articles. Articles that reported on neuropathy in phase III randomised control trials involving bortezomib in any treatment arm for the treatment of MM were included in this review. A total of 43 full text articles met criteria, which examined 23 phase III trials (N = 8218). Overall incidence of neuropathy ranged from 8.4% to 80.5% (median = 37.8%) and severe neuropathy (grade 3-4) ranged from 1% to 33.2% (median = 8%). Similar reports of neuropathy of any grade and severe neuropathy were observed between the newly diagnosed and relapsed cohort. Bortezomib regimens with reduced dose intensity were associated with reduced neuropathy incidence. Increased cumulative dosing levels, intravenous compared with subcutaneous administration and combination therapy with thalidomide were associated with higher rates of BIPN. This analysis revealed that BIPN is a significant toxicity. More sensitive measures are required to capture the incidence and severity of BIPN. Better understanding of risk factors and reversibility profiles will minimise the number of cancer survivors living with residual treatment side effects.

Recruitment of interneuronal circuits generating later indirect (I) waves seem to be important in short-interval intracortical inhibition (SICI) and facilitation (SICF) development. This study assessed whether individual variations in intracortical inhibition and facilitation could be explained by variation in recruitment of interneuronal networks.Cortical excitability was assessed using a figure of eight coil, with motor evoked responses recorded over the contralateral abductor pollicis brevis (APB) muscle. I-wave recruitment was inferred from the measurement of motor evoked potential (MEP) onset latencies, with coil positioned in posterior-to-anterior (early I waves) and anterior-to-posterior (later I waves) directions.Subtle variability in the recruitment of later I-waves (I3) was evident across subjects. Importantly, mean SICI (P 0.05) was significantly greater in subjects recruiting I3 waves, as were the two SICI peaks at interstimulus intervals of 1 ms (P 0.05) and 3 ms (P 0.05). In addition, mean SICF was significantly greater in participants exhibiting an AP-to-LM latency differences of4 ms (P 0.01). There was no significant correlation between I-wave recruitment and intracortical facilitation, motor evoked potential amplitude or cortical silent period duration.Differential recruitment of interneuronal networks appears to underlie the generation and individual variations in intracortical inhibition and facilitation.Investigating cortical interneuronal networks in human diseases may yield novel pathophysiological insights.

To characterise the regional cortical patterns underlying clinical symptomatology in amyotrophic lateral sclerosis (ALS).138 patients prospectively underwent transcranial magnetic stimulation studies from hand and leg cortical regions of each hemisphere, obtaining motor evoked potentials from all four limbs. Patients were categorised by clinical phenotype and underwent clinical and peripheral evaluation of disease.Cortical dysfunction was evident across the motor cortices, with reduction in short-interval intracortical inhibition (SICI) suggesting the presence of widespread cortical hyperexcitability, most prominently from clinically affected regions (hand p 0.0001; leg p 0.01). In early disease, cortical abnormalities were asymmetric between hemispheres, focally corresponding to clinical site-of-onset (p 0.05). Degrees of cortical dysfunction varied between phenotypes, with the bulbar-onset cohort demonstrating greatest reduction in SICI (p = 0.03).The pattern of cortical dysfunction appears linked to clinical evolution in ALS, with early focal asymmetry preceding widespread changes in later disease. Cortical differences across phenotypes may influence clinical variability.This is the first study to extensively map cortical abnormalities from multiple motor regions across hemispheres. The early cortical signature mirrors symptom laterality, supporting a discrete region of disease onset. Phenotypes appear to exist within a pathophysiological continuum, but cortical heterogeneity may mediate observed differences in clinical outcome.

AIMS To undertake sonographic assessment of nerve blood flow in people with Type 2 diabetes and correlate the findings with neuropathy severity scores and electrophysiological measurements. METHODS Median and tibial nerve ultrasound scans were undertaken in 75 people with diabetes and 30 aged-matched controls without diabetes, using a high-resolution linear probe at non-entrapment sites. Nerve blood flow was quantified using power Doppler techniques to obtain the vessel score and the maximum perfusion intensity. Neuropathy severity was assessed using a total neuropathy score. RESULTS Diabetic nerves had higher rates of nerve blood flow detection (28%) compared to the control group (P < 0.0001). Significant correlations were found between nerve blood flow measurements and nerve size (P

Objective: This study sought to investigate whether a multistep process was also evident in an Australian amyotrophic lateral sclerosis (ALS) population. Methods: Mortality rates for ALS patients (years 2007-2016) were obtained from the Australian Institute of Health and Welfare (AIHW). The log incidence of ALS, as reflected by crude mortality rates, was regressed against log of age disease onset. Results: From a total population of 24 million, 6524 cases of ALS were identified. A linear relation between the log incidence and log age was identified, with r2 value of 0.99, indicating that ALS is a multistep process. The linear slope estimate was 5.0, suggesting that six steps were required for development of ALS. Conclusions: This study established a linear relationship between log incidence and log age onset in an Australia ALS population, consistent with a multistep process. Identification of these steps will likely be of therapeutic benefit in ALS.

Despite 30 years of research there are still significant unknowns and controversies associated with multifocal motor neuropathy (MMN) including disease pathophysiology, diagnostic criteria and treatment. Foremost relates to the underlying pathophysiology, specifically whether MMN represents an axonal or demyelinating neuropathy and whether the underlying pathophysiology is focused at the node of Ranvier. In turn, this discussion promotes consideration of therapeutic approaches, an issue that becomes more directed in this evolving era of precision medicine. It is generally accepted that MMN represents a chronic progressive immune-mediated motor neuropathy clinically characterised by progressive asymmetric weakness and electrophysiologically by partial motor conduction block. Anti-GM1 IgM antibodies are identified in at least 40% of patients. There have been recent developments in the use of neuromuscular ultrasound and MRI to aid in diagnosing MMN and in further elucidation of its pathophysiological mechanisms. The present Review will critically analyse the knowledge accumulated about MMN over the past 30 years, culminating in a state-of-the-art approach to therapy.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder characterised by the loss of upper and lower motor neurons resulting in paralysis and eventual death. Approximately 10% of ALS cases have a family history of disease, while the remaining cases present as apparently sporadic. Heritability studies suggest a significant genetic component to sporadic ALS, and although most sporadic cases have an unknown genetic etiology, some familial ALS mutations have also been found in sporadic cases. This suggests that some sporadic cases may be unrecognised familial cases with reduced disease penetrance. Identifying a familial basis of disease in apparently sporadic ALS cases has significant genetic counselling implications for immediate relatives. A powerful strategy to uncover a familial link is identity-by-descent (IBD) analysis which detects genomic regions that have been inherited from a common ancestor. We performed IBD analysis on 90 Australian familial ALS cases from 25 families and three sporadic ALS cases, each of whom carried one of three SOD1 mutations (p.I114T, p.V149G and p.E101G). We identified five unique haplotypes that carry these mutations in our cohort, indicative of five founder events. This included two different haplotypes that carry SOD1 p.I114T, where one haplotype was present in one sporadic case and 20 families, while the second haplotype was found in the remaining two sporadic cases and one family, thus linking these familial and sporadic cases. Furthermore, we linked two families that carry SOD1 p.V149G and found that SOD1 p.E101G arose independently in each family that carries this mutation.

Frontotemporal dementia (FTD) refers to a group of progressive neurodegenerative disorders with different pathological signatures, genetic variability and complex disease mechanisms, for which no effective treatments exist. Despite advances in understanding the underlying pathology of FTD, sensitive and specific fluid biomarkers for this disease are lacking. As in other types of dementia, mounting evidence suggests that neuroinflammation is involved in the progression of FTD, including cortical inflammation, microglial activation, astrogliosis and differential expression of inflammation-related proteins in the periphery. Furthermore, an overlap between FTD and autoimmune disease has been identified. The most substantial evidence, however, comes from genetic studies, and several FTD-related genes are also implicated in neuroinflammation. This Review discusses specific evidence of neuroinflammatory mechanisms in FTD and describes how advances in our understanding of these mechanisms, in FTD as well as in other neurodegenerative diseases, might facilitate the development and implementation of diagnostic tools and disease-modifying treatments for FTD.

Neuroinflammation is an inflammatory response in the brain and spinal cord, which can involve the activation of microglia and astrocytes. It is a common feature of many central nervous system disorders, including a range of neurodegenerative disorders. An overlap between activated microglia, pro-inflammatory cytokines and translocator protein (TSPO) ligand binding was shown in early animal studies of neurodegeneration. These findings have been translated in clinical studies, where increases in TSPO positron emission tomography (PET) signal occur in disease-relevant areas across a broad spectrum of neurodegenerative diseases. While this supports the use of TSPO PET as a biomarker to monitor response in clinical trials of novel neurodegenerative therapeutics, the clinical utility of current TSPO PET radioligands has been hampered by the lack of high affinity binding to a prevalent form of polymorphic TSPO (A147T) compared to wild type TSPO. This review details recent developments in exploration of ligand-sensitivity to A147T TSPO that have yielded ligands with improved clinical utility. In addition to developing a non-discriminating TSPO ligand, the final frontier of TSPO biomarker research requires developing an understanding of the cellular and functional interpretation of the TSPO PET signal. Recent insights resulting from single cell analysis of microglial phenotypes are reviewed.

This month’s issue of the journal contains a manuscript from Professor James Lance,1 the final contribution to a partnership with the Journal of Neurology, Neurosurgery and Psychiatry (JNNP) that dates back over some 60 years of publications.2–21 Not only a fine researcher, Lance was an expert clinician and teacher, a true gentleman of neurology. The body of publications by Lance published in this journal mirrors his development as an academic neurologist, a career path that before Lance, had not been traversed in Australia. Lance started his mission as a postgraduate doctoral student in the fledgling brain research unit at the University of Sydney, with a particular focus on neurophysiology, then an emerging technology with as-yet unrealised potential applications to human disease. Lance’s initial studies focused on the pyramidal tract, and then on human movement and movement disorders, particularly relevant to his current publication in JNNP that postulates a contribution of myoclonus to the process of falls in the elderly. After completing MD by research, Lance moved to London, working at the Hammersmith Hospital and then the National Hospital for Neurology and Neurosurgery, Queen Square. During this period in London, Lance encountered Edward Arnold (EA) Carmichael, who had previously served as Editor-in-Chief of JNNP (1938–1948, having taken over from Kinnier Wilson).22 The friendship with Carmichael …

To assess the amount of phosphorylated and nonphosphorylated TAR DNA-binding protein 43 (TDP-43) in the motor brain regions of cases of amyotrophic lateral sclerosis (ALS) with and without repeat expansions in theThe 45-kDa phosphorylated form of TDP-43 and 43-kDa nonphosphorylated form of TDP-43 were quantified by immunoblot in postmortem brain tissue from the motor cortex, spinal cord, and cerebellar vermis of 23 cases with ALS with repeat expansions in theSignificantly greater levels of phosphorylated TDP-43 were identified in the motor cortex of cases with ALS withDespite its central role in the pathogenesis of ALS and the emergence of potential targets to modify its aggregation, TDP-43 levels have not been quantified in pathologically confirmed cases with ALS. The present results demonstrating significant differences in phosphorylated but not nonphosphorylated TDP-43 levels suggest that different posttranslational modifications are involved in the generation of greater pathologic TDP-43 levels identified here in our cohort of cases with genetic expansions. These findings are consistent with emerging studies implicating distinct pathomechanisms in the generation of pathologic TDP-43 in cases with ALS with

The cerebellum shows neuropathological change in a number of neurodegenerative conditions where clinical involvement is not the primary feature, including amyotrophic lateral sclerosis (ALS). Whether these changes are associated with disruption to the direct cerebellar tract pathways to the motor cortex and spinal cord in ALS is uncertain. Diffusion tensor imaging was used to examine the integrity of two primary cerebellar pathways, the dentato-rubro-thalamo-cortical (DRTC) and spino-cerebellar (SC) tracts. ALS patients with an upper motor neuron (UMN)-predominant phenotype (n = 9), were matched to a group with the UMN-only condition primary lateral sclerosis (PLS, n = 10) and healthy controls (n = 17). Significant alterations across diffusion metrics in the DRTC proximal to the motor cortex were found in both patient groups. PLS patients were found to have an independent diffusion abnormality in the cerebellar region of the DRTC and SC tracts. Disruption to primary cerebellar tracts in PLS is therefore postulated, adding to other markers of its divergent pathogenesis from ALS.

Amyotrophic lateral sclerosis (ALS) is an adult onset disease but with an increasingly recognized preclinical prodrome. A wide spectrum of investigative approaches has identified loss of inhibitory function at the heart of ALS. In developing an explanation for the onset of ALS, it remains a consideration that ALS has its origins in neonatal derangement of the γ-aminobutyric acid (GABA)-ergic system, with delayed conversion from excitatory to mature inhibitory GABA and impaired excitation/inhibition balance. If this is so, the resulting chronic excitotoxicity could marginalize cortical network functioning very early in life, laying the path for neurodegeneration. The possibility that adult-onset neurodegenerative conditions might have their roots in early developmental derangements is worthy of consideration, particularly in relation to current models of disease pathogenesis. Unraveling the very early molecular events will be crucial in developing a better understanding of ALS and other adult neurodegenerative disorders. Muscle Nerve, 2019.

Background: Neuroinflammation and human endogenous retroviruses (HERV-K) are thought to have a role in the pathophysiology of amyotrophic lateral sclerosis (ALS). Therapy directed against endogenous retroviruses has demonstrated positive effects during in-vitro and biomarker studies. Consequently, the present study was undertaken to assess the safety and tolerability of long-term Triumeq (abacavir, lamivudine and dolutegravir) exposure in patients with ALS and to assess efficacy against biomarkers of disease progression. Methods: Patients were observed during a 10-week lead-in period before receiving Triumeq treatment for 24 weeks at four specialist ALS centres. The primary outcomes were safety and tolerability. Secondary outcomes included HERV-K expression levels, urinary p75ECD levels, neurophysiological parameters and clinical outcomes. The ENCALS prediction model was applied to provide an estimate of the cohort survival. The trial was registered on www.clinicaltrials.gov (NCT02868580). Findings: 40 patients with ALS received Triumeq and 35 (88%) completed treatment. There were no drug-related serious adverse events; one patient was withdrawn from the study due to a drug-associated increase in liver enzymes. A favourable response on HERV-K expression levels was observed, accompanied by a potential slowing in ALSFRS-R progression rate of 21.8% (95% CI -4.8 %- 48.6%) and the amount of urinary p75ECD measured. One patient died five months after stopping treatment, while five were expected to have died during the treatment period (interquartile range 2-8). Interpretation: Long-term Triumeq exposure was safe and well tolerated. There was suggestive evidence for a biological response in pharmacodynamic and clinical biomarkers. A larger international phase III trial will be deployed to assess the effect of Triumeq on overall survival and disease progression. Funding: Funding was provided by the FightMND Foundation; MND Research Institute of Australia; MND Association, United Kingdom. ViiV Healthcare provided the Triumeq. Declaration of Interest: The authors have no conflict of interest with respect to the research or data presented in this study. No funder was involved in the study design or interpretation or reporting of the results. Ethical Approval: The relevant ethics committees at each site approved the protocol. The study was conducted in accordance with Good Clinical Practice (GCP) and the Declaration of Helsinki (2000). The trial was registered on clinicaltrials.gov (NCT02868580).

IntroductionThe majority of patients undergoing haemodialysis (HD) show evidence of uraemic neuropathy, a condition with no known disease-modifying treatments. The pathogenesis of uraemic neuropathy is poorly understood, but may be related to cumulative exposure to middle molecules or other solutes such as potassium. It is not known whether haemodiafiltration (HDF) reduces the progression of uraemic neuropathy.Methods and analysisFiltration In the Neuropathy of End-Stage kidney disease Symptom Evolution (FINESSE) is a multicentre, randomised, open-label, blinded endpoint assessment, controlled trial designed to assess the impact of HDF versus HD on uraemic neuropathy. Maintenance HD patients will be randomised in a 1:1 ratio to receive HDF or HD with high-flux membranes for 4 years. The primary endpoint is the difference in the mean change in Total Neuropathy Score (TNS)—a measure of peripheral neuropathy combining symptoms, signs and nerve conduction velocity—over the study period. Secondary outcomes include change at annual timepoints in the TNS and the Neuropathy Symptom Score; and in morbidity, mortality and safety events.Ethics and disseminationThe FINESSE trial has been approved by the Ethics Review Committee of the Sydney South West Area Health Service (HREC/09/RPAH/268) and of Adventist HealthCare Limited (2012–027). When published in a peer-reviewed journal, it will be the largest and longest reported randomised trial aimed at reducing the incidence and severity of uraemic neuropathy. It will advance the understanding of the natural history of uraemic neuropathy and the influence of convective therapies on both neurophysiological and clinical outcomes. It will also allow refinement of current hypotheses surrounding the pathogenesis of uraemic neuropathy and, most importantly, may lead to improvements in the lives of the many patients affected by this debilitating condition.Trial registration numberACTRN12609000615280.

Neuroethics is central to the Australian Brain Initiative’s aim to sustain a thriving and responsible neurotechnology industry. Diverse and inclusive community and stakeholder engagement and a trans-disciplinary approach to neuroethics will be key to the success of the Australian Brain Initiative. Refereed/Peer-reviewed

Objective While some regard an association between motor neuron disease (MND) and malignancy as co-incidental, others have argued that it could represent a distinct clinical entity. The present study undertook in depth phenotyping along with assessment of cortical function to further explore disease pathophysiology in MND with malignancy (MND-M) patients. Methods Clinical features along with assessment of peripheral and cortical function was undertaken in 13 MND-M and results were compared to sporadic and familial MND cohorts. Results From a cohort 13 patients (10 males; aged 65.2 ± 2.0 years), 38.5% were diagnosed with a haematological malignancy. The lower motor neuron phenotype predominated in the in the MND-M patients (χ2 = 10.8, P Conclusions The present study suggests that MND-M falls within the spectrum of MND. Significance The concept of a co-incidental association between MND and malignancy is supported through the present study by the presence of cortical dysfunction, combined with clinical findings that can be explained within the spectrum of abnormality evident in classical MND phenotypes.

Reactivation of Human Endogenous Retrovirus K (HERV-K), subtype HML-2, has been associated with pathophysiology of amyotrophic lateral sclerosis (ALS). We aimed to assess the efficacy of antiretroviral therapy in inhibiting HML-2 in patients with ALS and a possible association between the change in HML-2 levels and clinical outcomes. We studied the effect of 24-weeks antiretroviral combination therapy with abacavir, lamivudine, and dolutegravir on HML-2 levels in 29 ALS patients. HML-2 levels decreased progressively over 24 weeks (P = 0.001) and rebounded within a week of stopping medications (P = 0.02). The majority of participants (82%), defined as “responders”, experienced a decrease in HML-2 at week 24 of treatment compared to the pre-treatment levels. Differences in the evolution of some of the clinical outcomes could be seen between responders and non-responders: FVC decreased 23.69% (SE = 11.34) in non-responders and 12.71% (SE = 8.28) in responders. NPI score decreased 91.95% (SE = 6.32) in non-responders and 53.05% (SE = 10.06) in responders (P = 0.01). Thus, participants with a virological response to treatment showed a trend for slower progression of the illness. These findings further support the possible involvement of HML-2 in the clinical course of the disease.

IntroductionAmyotrophic lateral sclerosis (ALS) is an adult-onset, progressive and universally fatal neurodegenerative disorder. In Europe, Australia and Canada, riluzole is the only approved therapeutic agent for the treatment of ALS, while in the USA, riluzole and edaravone have been approved by the Food and Drug Administration (FDA) . Neither riluzole nor edaravone treatment has resulted in substantial disease-modifying effects. There is, therefore, an urgent need for drugs that result in safe and effective treatment. Here, we present the design and rationale for the phase 2 RESCUE-ALS study, investigating the novel nanocatalytic drug, CNM-Au8, as a therapeutic intervention that enhances the metabolic and energetic capacity of motor neurones. CNM-Au8 is an aqueous suspension of clean-surfaced, faceted gold nanocrystals that have extraordinary catalytic capabilities, that enhance efficiencies of key metabolic reactions, while simultaneously reducing levels of reactive oxygen species. This trial utilises a novel design by employing motor unit number index (MUNIX), measured by electromyography, as a quantitative measure of lower motor neurone loss and as an early marker of ALS disease progression.Methods and analysisThis is a multicentre, randomised, double-blind, parallel group, placebo-controlled study of the efficacy, safety, pharmacokinetics and pharmacodynamics of CNM-Au8 in ALS patients. Patients will be randomised 1:1 to either receive 30 mg of CNM-Au8 once daily or matching placebo over a 36-week double-blind treatment period. Efficacy will be assessed as the change in motor neurone loss as measured by electromyography (eg, MUNIX, the primary endpoint; and secondary endpoints including MScanFit, motor unit size index, Split Hand Index, Neurophysiology Index). Exploratory endpoints include standard clinical and quality of life assessments.Ethics and disseminationRESCUE-ALS was approved by the Western Sydney Local Health District Human Research Ethics Committee (Ethics Ref: 2019/ETH12107). Results of the study will be submitted for publication in a peer-reviewed journal.Trial registration numberNCT04098406

Axonal excitability testing provides in vivo assessment of axonal ion channel function and membrane potential. Excitability techniques have provided insights into the pathophysiological mechanisms underlying the development of neurodegeneration and clinical features of amyotrophic lateral sclerosis (ALS) and related neuromuscular disorders. Specifically, abnormalities of Na+ and K+ conductances contribute to development of membrane hyperexcitability in ALS, thereby leading to symptom generation of muscle cramps and fasciculations, in addition to promoting a neurodegenerative cascade via Ca2+-mediated processes. Modulation of axonal ion channel function in ALS has resulted in significant symptomatic improvement that has been accompanied by stabilization of axonal excitability parameters. Separately, axonal ion channel dysfunction evolves with disease progression and correlates with survival, thereby serving as a potential therapeutic biomarker in ALS. The present review provides an overview of axonal excitability techniques and the physiological mechanisms underlying membrane excitability, with a focus on the role of axonal ion channel dysfunction in motor neuron disease and related neuromuscular diseases.

OBJECTIVE The loss of autobiographical memories (ABM) is a pervasive feature of neurodegenerative diseases. Studies to date have not investigated ABM retrieval in amyotrophic lateral sclerosis (ALS), a multisystem disorder that may be associated with cognitive dysfunction and dementia. METHOD The integrity of autobiographical memory was evaluated in 22 ALS patients compared with 28 age-matched controls using the Autobiographical Interview (AI), a semistructured interview assessing autobiographical events from discrete time periods across the life span. RESULTS ABM retrieval was preserved in ALS and remained rich in detail for personal events in recent (last 12-months) and remote (teenage years) time epochs. ABM retrieval was positively correlated with months since ALS symptom onset, with a greater number of contextual details being recalled as ALS progressed. A shift in how ABMs were perceived in ALS patients became apparent, with more recurrent reflection of recent life, which was also weighted with greater personal importance. CONCLUSION The preservation of ABM in ALS has clinical implications for the use of life review as a therapeutic tool in a multidisciplinary care setting. (PsycINFO Database Record

To assess the sensitivity and specificity of the Awaji and revised El Escorial diagnostic criteria (rEEC) in amyotrophic lateral sclerosis (ALS).We conducted a large prospective multicenter study, recruiting 416 patients (253 male, 163 female) between January 1, 2012, and August 31, 2015, to compare the diagnostic accuracy of Awaji and rEEC in accordance with standards of reporting of diagnostic accuracy criteria.The sensitivity of the Awaji criteria (57%, 50.0%-63.3%) was higher when compared to rEEC (45%, 38.7%-51.7%, p0.001), translating to a 12% gain in sensitivity. The specificity of the both criteria were identical, 99.5%, indicating the number needed to test in order to diagnose one extra case of ALS was 1.8 (1.5-2) for Awaji criteria and 2.4 (2-2.6) for rEEC. The Awaji criteria exhibited a higher sensitivity across subgroups, including bulbar (p0.001) and limb-onset (p0.001) patients. The inclusion of the possible diagnostic category as a positive finding enhanced sensitivity of the Awaji criteria and rEEC, particularly in early stages of ALS, while maintaining specificity.The present study established a higher sensitivity of Awaji criteria when compared to rEEC, with diagnostic benefits evident in bulbar and limb-onset disease. Inclusion of possible as a positive finding enhanced sensitivity of both criteria, while maintaining specificity, and should be considered in clinical practice and future therapeutic trials.This study provides Class IV evidence that the Awaji criteria have a higher sensitivity and the same specificity as the rEEC in identifying patients with ALS.

To study the relationship between cortical function and survival in amyotrophic lateral sclerosis (ALS).A total of 216 referrals were screened, and participants with familial ALS or an inexcitable cortex were excluded. Clinical measures and phenotyping from 169 patients with sporadic ALS were combined with an assessment of cortical function using threshold tracking transcranial magnetic stimulation with indices including short interval intracortical inhibition (SICI). Peripheral nerve studies were collected, incorporating compound muscle action potential amplitude. Clinical prognostic factors were recorded longitudinally, including ALS Functional Rating Scale-Revised (ALSFRS-R).Compared to 109 healthy controls, 169 patients had reduced SICI (p0.0001). In survival analysis, 105 patients progressed to death with an estimated median survival time of 37 months. In patients with less than 2 years disease duration (n = 140), those with bulbar onset (p = 0.017), rapid vital capacity (VC) decline (p0.0001), rapid ALSFRS-R decline (p0.0001), and reduced averaged SICI (p = 0.047) had a poorer prognosis. Multivariate analysis identified rapid VC decline (p0.0001), rapid ALSFRS-R decline (p = 0.0060), and reduced averaged SICI (p = 0.011) as factors independently associated with a shorter survival.Cortical dysfunction appears to be a prognostic marker in patients with ALS within 2 years of disease onset, such that patients with reduced averaged SICI, indicative of intracortical hyperexcitability, demonstrated a worse prognosis.

To investigate the effects of fampridine on nerve excitability, the present study utilized peripheral axonal excitability techniques in 18 MS patients receiving treatment with fampridine.Studies were performed at baseline and repeated 3months after institution of fampridine at standard dosing.Following treatment with fampridine there were significant changes in axonal excitability for those parameters associated with fast K(+) channels that shifted towards normal control values. Specifically, increases were noted in the peak superexcitability of recovery cycle (fampridine, -25.6±1.6%; baseline -22.8±1.7%; p0.004), peak depolarizing threshold electrotonus (fampridine, 69.1±1.0%; baseline 67.0±1.4%; p0.004), and depolarizing threshold electrotonus between 40 and 60ms after onset of depolarization (fampridine, 52.8±1.3%; baseline 49.9±1.4%; p=0.02).The present study has established that fampridine at standard doses exerts effects on peripheral nerve function that may be mediated by reduction of fast K(+) conductances.Modulation of fast K(+) conductances by fampridine may contribute to the improvement observed in MS symptoms including motor fatigue.

It is increasingly recognized that metabolic factors influenced by eating behavior, may affect disease progression in neurodegeneration. In frontotemporal dementia (FTD), which shares a significant overlap with Amyotrophic lateral sclerosis (ALS), patients are well known to develop changes in eating behavior. Whether patients with pure ALS and those with cognitive and behavioral changes associated with ALS also develop similar changes is not known. The current study aimed to examine caloric intake, eating behavioral changes, body mass index, and using cox regression analyses survival across the spectrum of 118 ALS-FTD patients (29 pure ALS, 12 ALS-plus and 21 ALS-FTD, 56 behavioral variant FTD), compared with 25 control subjects. The current study found contrary to previous assumptions eating changes are not restricted to FTD, but a spectrum of eating behavioral changes occur in ALS, present in those with pure ALS and worsening as patients develop cognitive changes. ALS patients with cognitive impairment exhibited changes in food preference, with caloric intake and BMI increasing with the development of cognitive/behavioral changes. Both pure ALS and those with cognitive impairment demonstrated increased saturated fat intake. Survival analyses over the mean patient follow-up period of 6.9 years indicated that increasing eating behavioral changes were associated with an improved survival (threefold decrease risk of dying). Changes in eating behavior and metabolism occur in ALS in association with increasing cognitive impairment, perhaps exerting a protective survival influence. These changes provide insights into the common neural networks controlling eating and metabolism in FTD and ALS and provide potential targets to modify disease prognosis and progression.

Objective Recently, the utility of threshold tracking paired-pulse transcranial magnetic stimulation (TTTMS), to measure changes in cortical excitabilitability, has been established for diagnostic purposes across a range of neurological diseases. However, the impact of healthy aging on the GABA-ergic intracortical inhibitory system remains unclear. To improve the clinical applicability, TTTMS was performed across an age spectrum. Methods TTTMS, single-pulse TMS and nerve conduction studies (NCS) were performed in 113 healthy subjects aged between 20 and 83 years (57 male and 56 female). Results Prolonged motor evoked potential (MEP) latency, increased central motor conduction time, decreased compound muscle action potential (CMAP) amplitude, prolonged F-wave latency and decreased neurophysiological index (NI), calculated from CMAP amplitude, latency and F-wave frequency, were observed as subjects aged. In contrast, short interval intracortical inhibition (SICI) and facilitation did not change. Compared to females, males exhibited a reduced SICI and NI along with longer MEP, CMAP with prolonged F-wave latencies. Multivariate analyses revealed similar results. Conclusion Utilizing clinically applicable TTTMS protocols, findings suggest that GABA mediated intracortical inhibition may be greater in females but does not significantly change with age. Significance These findings may better inform the interpretation of diagnostic TTTMS studies in the clinical setting.

Axonal injury is the pathological correlate of fixed disability in the inflammatory demyelinating disorders of the central and peripheral nervous system. The mechanisms that initiate and propagate neurodegeneration in these conditions are poorly understood, and a lack of available neuroprotective and proreparative therapies represent a significant unmet clinical need. In this article, we review new data pertaining to the convergent and divergent immunological, cellular, and molecular mechanisms that underpin neurodegeneration in multiple sclerosis and the chronic inflammatory demyelinating neuropathies that will inform the development of targeted therapies.New insights have been gained from recognition of the axon as an integral component of the axon-myelin unit, identification of defects in axonal transport, elucidation of mechanisms of Wallerian degeneration and, in the central nervous system, the appreciation of trans-synaptic axonal degeneration, and widespread cortical synaptopathy. Concurrently, specific immune triggers of axonal injury, particularly in the peripheral immune system; and inhibitors of repair and regrowth, have been identified.Neurodegeneration is a critical determinant of disability in the inflammatory demyelinating diseases of both the central nervous system and peripheral nervous system. Current therapies are restricted to agents that (effectively) treat the inflammatory components of these conditions. Although propagated, and in some instances triggered, by inflammation, axon damage will in future years be treated or prevented with adjuvant, targeted therapies that exploit emerging pathways to neurodegeneration.

INTRODUCTION There is no specific treatment for neuropathy in chronic kidney disease (CKD). We compared nerve function across hemodialysis (HD) and peritoneal dialysis (PD). METHODS Subjects underwent neurological assessment and neurophysiological testing using nerve excitability studies. Pre- and postdialysis studies were undertaken in HD (n = 10) and PD (n = 10) patients and were compared with stage 4 CKD patients (n = 12) and healthy controls (n = 20). RESULTS There were prominent differences in nerve excitability between the groups (P

Neurodegeneration refers to a heterogeneous group of brain disorders that progressively evolve. It has been increasingly appreciated that many neurodegenerative conditions overlap at multiple levels and therefore traditional clinicopathological correlation approaches to better classify a disease have met with limited success. Neuronal network disintegration is fundamental to neurodegeneration, and concepts based around such a concept may better explain the overlap between their clinical and pathological phenotypes. In this Review, promoters of overlap in neurodegeneration incorporating behavioural, cognitive, metabolic, motor, and extrapyramidal presentations will be critically appraised. In addition, evidence that may support the existence of large-scale networks that might be contributing to phenotypic differentiation will be considered across a neurodegenerative spectrum. Disintegration of neuronal networks through different pathological processes, such as prion-like spread, may provide a better paradigm of disease and thereby facilitate the identification of novel therapies for neurodegeneration.

Sleep disorders in amyotrophic lateral sclerosis (ALS) present a significant challenge to the management of patients. Issues include the maintenance of adequate ventilatory status through techniques such as non-invasive ventilation, which has the ability to modulate survival and improve patient quality of life. Here, a multidisciplinary approach to the management of these disorders is reviewed, from concepts about the underlying neurobiological basis, through to current management approaches and future directions for research.

Objectives Diabetic neuropathy is a debilitating complication of diabetes. Animal models of type 1 diabetes (T1DM) suggest that functional and structural changes, specifically axo-glial dysjunction, may contribute to neuropathy development. The present study sought to examine and characterise early sensory axonal function in T1DM patients in the absence of clinical neuropathy. Methods Thirty patients with T1DM (15M:15F) without neuropathy underwent median nerve sensory and motor axonal excitability studies to examine axonal function. A verified mathematical model of human motor and sensory axons was used to elucidate the underlying causes of observed alterations. Results Compared to controls (NC), T1DM patients demonstrated significant axonal excitability abnormalities in sensory and motor axons. These included marked reductions in sensory and motor subexcitability during the recovery cycle (T1DM 7.9 ± 0.4:10.4 ± 0.6%, NC 10.4 ± 0.7:15.4 ± 1.2%, P 0.01) and during hyperpolarizing threshold electrotonus at 10–20 ms (T1DM −75.5 ± 0.8:−69.7 ± 0.8%, NC −78.4 ± 1:−72.7 ± 0.9%, P 0.01). Mathematical modelling demonstrated that these changes were due to reduced nodal Na + currents, nodal/paranodal K + conductances and Na + /K + pump dysfunction, consistent with axo-glial dysjunction as outlined in animal models of T1DM. Conclusions The study provided support for the occurrence of early changes in nodal and paranodal conductances in patients with T1DM. Significance These data indicate that axonal excitability techniques may detect early changes in diabetic patients, providing a window of opportunity for prophylactic intervention in T1DM.

Background: Apathy is the most commonly reported behavioural change in amyotrophic lateral sclerosis (ALS). However, the degree to which it affects prognosis and overlaps with depression in this population is unknown. The present study examined the relationship between level of apathy, mortality and survival time and whether apathy was linked to specific symptom clusters of depression. Methods: A cohort of 76 consecutive ALS patients attending specialised multidisciplinary clinics were classified according to level of apathy. The effect of clinical factors and apathy on survival time were analysed using univariate and multivariate methods. Results: The majority of patients with moderate-severe apathy died during the study (P = 0.003) and had a median survival time of 21.7 months, considerably shorter than patients with mild apathy (46.9 months) and no apathy (51.9 months) (P = 0.0001). Apathy remained a significant predictor of survival even after controlling for clinical factors and symptom duration at the time of study entry (hazard ratio 3.8, 95% confidence interval 1.9-7.5, P = 0.0001). Depression with demoralisation was not associated with level of apathy (P = 0.172) whereas depression with anhedonia was more common in patients with apathy than in those without apathy (P = 0.006). Conclusions: The presence of severe apathy is an independent, negative prognostic factor in ALS.

Objective Despite evidence suggesting that the cerebellum may be targeted in amyotrophic lateral sclerosis (ALS), particularly in cases with repeat expansions in the ATXN2 and C9ORF72 genes, the integrity of cerebellar neurons has yet to be examined. The present study undertakes a histopathological analysis to assess the impact of these repeat expansions on cerebellar neurons and determine whether similar cerebellar pathology occurs in sporadic disease. Methods Purkinje and granule cells were quantified in the vermis and lateral cerebellar hemispheres of ALS cases with repeat expansions in the ATXN2 and C9ORF72 genes, sporadic disease, and sporadic progressive muscular atrophy with only lower motor neuron degeneration. Results ALS cases with intermediate repeat expansions in the ATXN2 gene demonstrate a significant loss in Purkinje cells in the cerebellar vermis only. Despite ALS cases with expansions in the C9ORF72 gene having the highest burden of inclusion pathology, no neuronal loss was observed in this group. Neuronal numbers were also unchanged in sporadic ALS and sporadic PMA cases. Interpretation The present study has established a selective loss of Purkinje cells in the cerebellar vermis of ALS cases with intermediate repeat expansions in the ATXN2 gene, suggesting a divergent pathogenic mechanism independent of upper and lower motor neuron degeneration in ALS. We discuss these findings in the context of large repeat expansions in ATXN2 and spinocerebellar ataxia type 2, providing evidence that intermediate repeats in ATXN2 cause significant, albeit less substantial, spinocerebellar damage compared with longer repeats in ATXN2. Ann Neurol 2016;79:295–305

Objective Brown–Vialetto–Van Laere (BVVL) syndrome is a progressive motor and sensory neuronopathy secondary to mutations in SLC52A2 encoding the riboflavin transporter type 2 (RFVT2). The phenotype is characterized by early childhood onset hearing loss and sensory ataxia followed by progressive upper limb weakness, optic atrophy, bulbar weakness and respiratory failure. To gain further insight into disease pathophysiology and response to riboflavin supplementation, the present study investigated whether axonal ion channel or membrane abnormalities were a feature of BVVL. Methods Axonal excitability studies and clinical assessments were prospectively undertaken on six patients with BVVL secondary to riboflavin transporter deficiency type 2 (age range 10–21years) at baseline and after 12months of riboflavin (1000mg daily) therapy. Results At baseline, depolarizing and hyperpolarizing threshold electrotonus was ‘fanned out' and superexcitability was increased, while the resting current–threshold gradient and refractoriness were significantly reduced in BVVL patients when compared to controls. Mathematical modeling suggested that functional alterations of myelin underlay these findings with an increase in myelin permeability. Riboflavin therapy resulted in partial normalization of the axonal excitability findings, paralleled by maintenance of muscle strength. Conclusions The present study established that abnormalities in myelin permeability at the paranode was a feature of BVVL and were partially normalized with riboflavin therapy. Significance This study reveals a novel pathophysiological process for motor nerve dysfunction in BVVL. It also indicates that nerve excitability studies may be further developed in larger cohorts as a potential biomarker to identify treatment response for BVVL patients.

Estimating survival in amyotrophic lateral sclerosis (ALS) is challenging due to heterogeneity in clinical features of disease and a lack of suitable markers that predict survival. Our aim was to determine whether scoring of upper or lower motor neuron weakness is associated with survival. With this objective, 161 ALS subjects were recruited from two tertiary referral centres. Scoring of upper (UMN) and lower motor neuron (LMN) signs was performed, in addition to a brief questionnaire. Subjects were then followed until the censorship date. Univariate analysis was performed to identify variables associated with survival to either non-invasive ventilation (NIV) or death, which were then further characterized using Cox regression. Results showed that factors associated with reduced survival included older age, bulbar and respiratory involvement and shorter diagnostic delay (all p

Background and aims: Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) represent a disease spectrum. Caregiver burden in subtypes of FTD has not yet been directly compared with those patients who have co-existent FTD and ALS (ALSFTD). Method: Perceived caregiver burden was evaluated using the short Zarit Burden Interview (ZBI) in patients with behavioral-variant FTD (bvFTD, n = 21), semantic dementia (SD, n = 18), and ALSFTD (n = 15) at the initial clinical presentation and follow-up assessments. The Mini-Addenbrooke’s Cognitive Examination (M-ACE) and the Motor Neuron Disease Behaviour Scale (MiND-B) were also used. Linear mixed effects models examined longitudinal changes on the ZBI, M-ACE, and MiND-B across groups. Results: Burden at baseline was highest for the bvFTD group. Longitudinally, perceived burden increased for the SD and ALSFTD groups whereas in bvFTD, the level of burden which was high at baseline and remained high with disease progression. The severity of abnormal behaviors at baseline, as assessed by the MiND-B, correlated with baseline levels of caregiver burden and further accounted for 23% of the variance in caregiver burden at clinical follow-up. Conclusions: The trajectory of perceived burden differs across the FTD-ALS spectrum, with SD and ALSFTD caregivers demonstrating an increased burden that develops over time, compared to a persistently high level for bvFTD caregivers, evident throughout the disease course. The evolution of burden in these three syndromes likely reflects the initial presentation and clinical characterization that develops with time. Psycho-education programs for caregivers, which provide better coping strategies for challenging behaviors, may reduce levels of burden experienced with disease progression.

Background: Abnormalities in membrane excitability and Na+ channel function are characteristic of amyotrophic lateral sclerosis (ALS). We aimed to examine the neuroprotective potential, safety and tolerability of the Na+ channel blocker and membrane stabiliser flecainide in ALS. Methods: A double-blind, placebo-controlled, randomised clinical trial of flecainide (200 mg/day) for 32-weeks with a 12-week lead-in phase was conducted in participants with probable or definite ALS recruited from multiple Australian centres (ANZCT Registry number ACTRN12608000338369). Patients were reviewed by a cardiologist to rule out cardiac contraindications. Participants were randomly assigned (1:1) to flecainide or placebo using stratified permuted blocks by a central pharmacy. The primary outcome measure was the slope of decline of the ALS Functional Rating Scale-revised (ALS FRS-r) during the treatment period. Findings: Between March 11, 2008 and July 1, 2010, 67 patients were screened, 54 of whom were randomly assigned to receive flecainide (26 patients) or placebo (28 patients). Four patients in the flecainide group and three patients in the placebo group withdrew from the study. One patient in the flecainide group died during the study, attributed to disease progression. Flecainide was generally well tolerated, with no serious adverse events reported in either group. There was no significant difference in the rate of decline in the primary outcome measure ALS-FRS-r between placebo and flecainide treated patients (Flecainide 0.65 [95% CI 0.49 to 0.98]; Placebo 0.81 [0.49 to 2.12] P = 0.50). However, the rate of decline of the neurophysiological index was significantly reduced in the flecainide group (Flecainide 0.06 [0.01 to 0.11]; Placebo 0.14 [0.09 to 0.19], P = 0.02). Placebo-treated patients demonstrated greater CMAP amplitude reduction during the course of the study in the subset of patients with a reduced baseline CMAP amplitude (Flecainide: −15 ± 12%; Placebo −59 ± 12%; P = 0.03). Flecainide-treated patients maintained stabilized peripheral axonal excitability over the study compared to placebo. Interpretation: This pilot study indicated that flecainide was safe and potentially biologically effective in ALS. There was evidence that flecainide stabilized peripheral axonal membrane function in ALS. While the study was not powered to detect evidence of benefit of flecainide on ALS-FRS-r decline, further studies may demonstrate clinical efficacy of flecainide in ALS.

A key facet for the establishment of tailored intervention strategies directed against disease relates to the identification of patient subgroups and phenotypes which may then be utilised to predict individual treatment response and suggest future care approaches. Comprehensive clinical phenotyping is essential to reach an early and accurate diagnosis, and for mapping subsequent patterns of progression.1 It further serves to identify correlation between the variables of clinical presentation and disease burden, potentially enabling biomarker development.2 In turn, comprehensive patient phenotyping may assist in the stratification necessary to identify which patients may benefit most from a specific intervention.3 With these concepts in mind, the study by Goutman and colleagues delineates a role for advanced metabolomic analyses to gain insight into …

Late last year, the Journal of Neurology, Neurosurgery and Psychiatry ( JNNP ) polled readers, asking them to nominate the single most important or transformative development in neurology, neurosurgery or psychiatry in the past 100 years. The response was overwhelming! Would the early foundational work in brain imaging or drug therapies1–4 take centre stage? Did the phenomenal advancements in genetic research5–7 or the discovery of new biological pathways8 make the grade? Perhaps the discovery of ion channels, the …

BACKGROUND Amyotrophic lateral sclerosis (ALS) is a progressive and fatal neurodegenerative disorder of the human motor system. Neuroinflammation appears to be an important modulator of disease progression in ALS. Specifically, reduction of regulatory T cell (Treg) levels, along with an increase in pro-inflammatory effector T cells, macrophage activation and upregulation of co-stimulatory pathways have all been associated with a rapid disease course in ALS. Autologous infusion of expanded Tregs into sporadic ALS patients, resulted in greater suppressive function, slowing of disease progression and stabilization of respiratory function. Tecfidera (dimethyl fumarate) increases the ratio of anti-inflammatory (Treg) to proinflammatory T-cells in patients with relapsing remitting multiple sclerosis and rebalances the regulatory: inflammatory axis towards a neuroprotective phenotype. Consequently, the aim of this study was to assess the efficacy, safety, and tolerability of Tecfidera in sporadic ALS. METHODS The study is an investigator led Phase 2 multi-center, randomized, placebo controlled, double blind clinical trial assessing the efficacy and safety of Tecfidera in patients with sporadic ALS. The study duration is 40 weeks, with a 36-week study period and end of study visit occurring at 40 weeks or at early termination/withdrawal from study. The TEALS study has been registered with the Australian and New Zealand Clinical Trials registry (ANZCTR) under the trials registration number ACTRN12618000534280 and has been approved by the Human Research Ethics Committee and Research Governance Office at the lead site (Westmead Hospital) with the ethics number HREC/17/WMEAD/353. The participating sites have obtained site specific ethics and governance approvals from the local institution. RESULTS The primary endpoint is slowing of disease progression as reflected by the differences in the ALS Functional Rating Score-Revised (ALSFRS-R) score at Week 36. The secondary endpoints will include effects in survival, lower motor neuron function, respiratory function, quality of life and safety. CONCLUSION This Phase 2 multi-center, randomized, placebo controlled, double blind clinical trial will provide evidence of efficacy and safety of Tecfidera in sporadic ALS.

© 2019 Elsevier Inc. Neuroethics is central to the Australian Brain Initiative's aim to sustain a thriving and responsible neurotechnology industry. Diverse and inclusive community and stakeholder engagement and a trans-disciplinary approach to neuroethics will be key to the success of the Australian Brain Initiative.