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Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) lie at opposing ends of a clinical, genetic, and neuropathological continuum. In the last decade, it has become clear that cognitive and behavioral changes in patients with ALS are more frequent than previously recognized. Significantly, these non-motor features can impact the diagnosis, prognosis, and management of ALS. Partially overlapping neuropathological staging systems have been proposed to describe the distribution of TAR DNA-binding protein 43 (TDP-43) aggregates outside the corticospinal tract. However, the relationship between TDP-43 inclusions and neurodegeneration is not absolute and other pathophysiological processes, such as neuroinflammation (with a prominent role of microglia), cortical hyperexcitability, and synaptic dysfunction also play a central role in ALS pathophysiology. In the last decade, imaging and biofluid biomarker studies have revealed important insights into the pathophysiological underpinnings of extra-motor neurodegeneration in the ALS-FTLD continuum. In this review, we first summarize the clinical and pathophysiological correlates of extra-motor neurodegeneration in ALS. Next, we discuss the diagnostic and prognostic value of biomarkers in ALS and their potential to characterize extra-motor neurodegeneration. Finally, we debate about how biomarkers could improve the diagnosis and classification of ALS. Emerging imaging biomarkers of extra-motor neurodegeneration that enable the monitoring of disease progression are particularly promising. In addition, a growing arsenal of biofluid biomarkers linked to neurodegeneration and neuroinflammation are improving the diagnostic accuracy and identification of patients with a faster progression rate. The development and validation of biomarkers that detect the pathological aggregates of TDP-43 in vivo are notably expected to further elucidate the pathophysiological underpinnings of extra-motor neurodegeneration in ALS. Novel biomarkers tracking the different aspects of ALS pathophysiology are paving the way to precision medicine approaches in the ALS-FTLD continuum. These are essential steps to improve the diagnosis and staging of ALS and the design of clinical trials testing novel disease-modifying treatments.

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Altres ajuts: We thank the staff of the Department of Psychiatry of Hospital Universitari Santa Maria, Lleida; Núria Vidal D.Clin.Psy, (funded by a Spanish FIS-MSC Grant [PI11/01956]), from Hospital FREMAP Barcelona, Catalonia, Spain, who performed cognitive assessments;E. Vieta thanks the support of the Spanish Ministry of Economy and Competitiveness (PI15/00283) integrated into the Plan Nacional de I + D+I and cofinanced by ISCIII-Subdirección General de Evaluación y el Fondo Europeo de Desarrollo Regional (FEDER); CIBERSAM; M.J. Portella thanks the suport of the Catalan Department of Health (SLT006_17_177).We also thank the patients and healthy controls who participated in the study for their kind cooperation. We also thank to Rebecca Oglesby MD, who kindly helped us with the language editing. Objective Mutations in CD59 cause CIDP-like polyneuropathy in children with inherited chronic hemolysis. We hypothesized that mutations in CD59 might be found in a subset of sporadic CIDP patients. Methods 35 patients from two centers, fulfilling the EFNS/PNS diagnostic criteria for CIDP were included. CD59 coding region was amplified by PCR and Sanger sequenced. Results One rare variant was detected in a patient which resulted in a synonymous change and predicted to be neutral. Pathogenic variants were absent in our cohort. Interpretation Our pilot study suggests that mutations in CD59 are absent in adult-onset sporadic CIDP.

Altres ajuts: The Catalan frontotemporal initiative (CATFI) is funded by the Health Department of the Government of Catalonia (grant PERIS SLT002/16/00408 to Alberto Lleó and Raquel Sánchez-Valle). This work was also supported by research grants from the CIBERNED Program (Program 1, Alzheimer Disease to Alberto Lleó and SIGNAL study, file://www.signalstudy.es), partly funded by Fondo Europeo de Desarrollo Regional (FEDER), Unión Europea, "Una manera de hacer Europa." This work has also been supported by a "Marató TV3" grant (20141210 to Juan Fortea, 044412 to Rafael Blesa, 20143710 to Ricard Rojas-García and 20143810 to Raquel Sánchez-Valle) and Fundación BBVA (grant to A. Lleó) and a grant from the Fundació Bancaria La Caixa to Rafael Blesa. Ignacio Illán-Gala and Sergi Borrego-Écija are supported by the Rio Hortega grant from "Acción estratégica en Salud 2013-2016" and the European Social Fund. Ignacio Illán-Gala is supported by the Global Brain Health Institute (Atlantic Fellow for Equity in Brain Health). We acknowledge all the participants in this study and all the collaborators of the SPIN cohort. We also acknowledge Soraya Torres and Laia Muñoz for technical assistance. We thank EUROIMMUN for providing Aβ1-38 and Aβ1-40 ELISA assays for this study. Objective: We aimed to investigate the relationship between cerebrospinal fluid levels (CSF) of amyloid precursor protein (APP)-derived peptides related to the amyloidogenic pathway, cortical thickness, neuropsychological performance, and cortical gene expression profiles in frontotemporal lobar degeneration (FTLD)-related syndromes, Alzheimer's disease (AD), and healthy controls. Methods: We included 214 participants with CSF available recruited at two centers: 93 with FTLD-related syndromes, 57 patients with AD, and 64 healthy controls. CSF levels of amyloid β (Aβ)1-42, Aβ1-40, Aβ1-38, and soluble β fragment of APP (sAPPβ) were centrally analyzed. We compared CSF levels of APP-derived peptides between groups and, we studied the correlation between CSF biomarkers, cortical thickness, and domain-specific cognitive composites in each group. Then, we explored the relationship between cortical thickness, CSF levels of APP-derived peptides, and regional gene expression profile using a brain-wide regional gene expression data in combination with gene set enrichment analysis. Results: The CSF levels of Aβ1-40, Aβ1-38, and sAPPβ were lower in the FTLD-related syndromes group than in the AD and healthy controls group. CSF levels of all APP-derived peptides showed a positive correlation with cortical thickness and the executive cognitive composite in the FTLD-related syndromes group but not in the healthy control or AD groups. In the cortical regions where we observed a significant association between cortical thickness and CSF levels of APP-derived peptides, we found a reduced expression of genes related to synaptic function. Interpretation: APP-derived peptides in CSF may reflect FTLD-related neurodegeneration. This observation has important implications as Aβ1-42 levels are considered an indirect biomarker of cerebral amyloidosis.

Objective To investigate the clinical utility of 3 CSF biomarkers along the clinical spectrum of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Methods We analyzed 3 CSF biomarkers: the soluble beta-fragment of amyloid precursor protein (sAPP beta), YKL-40, and neurofilament light (NfL) in FTD (n = 86), ALS (n = 38), and a group of age-matched cognitively normal controls (n = 49). Participants with FTD with a CSF profile of Alzheimer disease were excluded. We compared cross-sectional biomarker levels between groups, studied their correlation with cognitive and functional scales (global cognitive z score, frontotemporal lobar degeneration Clinical Dementia Rating, revised ALS Functional Rating Scale, and ALS progression rate), survival, and cortical thickness. Results We found increased levels of YKL-40 and decreased levels of sAPP beta in both FTD and ALS groups compared to controls. The lowest sAPP beta levels and sAPP beta/YKL-40 ratio were found in the FTD group. In FTD, sAPP beta and the sAPP beta/YKL-40 ratio correlated with the disease severity. In the whole ALS-FTD spectrum, NfL levels and the NfL: sAPP beta ratio correlated with global cognitive performance (r = -0.41, p < 0.001 and r = -0.44, p < 0.001, respectively). In the ALS group, YKL-40 correlated with disease progression rate (r = 0.51, p = 0.001) and was independently associated with shorter survival. In both FTD and ALS groups, the sAPP beta/YKL-40 ratio showed a positive correlation with cortical thickness in frontotemporal regions. Conclusions sAPP beta, YKL-40, and NfL could represent valuable tools for the staging and prognosis of patients within the ALS-FTD clinical spectrum. Classification of evidence This study provides Class III evidence that CSF levels of sAPP beta, YKL-40, and NfL are useful to assess frontotemporal neurodegeneration and the progression rate in the ALS-FTD continuum.

The chronic inflammatory neuropathies (CINs) are rare, very disabling autoimmune disorders that generally respond well to immune therapies such as intravenous immunoglobulin (IVIg). The most common forms of CIN are chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), multifocal motor neuropathy, and polyneuropathy associated with monoclonal gammopathy of unknown significance. The field of CIN has undergone a major advance with the identification of IgG4 autoantibodies directed against paranodal proteins in patients with CIDP. Although these autoantibodies are only found in a small subset of patients with CIDP, they can be used to guide therapeutic decision-making, as these patients have a poor response to IVIg. These observations provide proof of concept that identifying the target antigens in tissue-specific antibody-mediated autoimmune diseases is important, not only to understand their underlying pathogenic mechanisms, but also to correctly diagnose and treat affected patients. This state-of-the-art Review focuses on the role of autoantibodies against nodes of Ranvier in CIDP, a clinically relevant emerging field of research. The role of autoantibodies in other immune-mediated neuropathies, including other forms of CIN, primary autoimmune neuropathies, neoplasms, and systemic diseases that resemble CIN, are also discussed.

Objective: To describe the frequency and clinical characteristics of patients referred to a tertiary neuromuscular clinic as having amyotrophic lateral sclerosis (ALS) but who were re-diagnosed as having an ALS mimic syndrome, and to identify the reasons that led to the revision of the diagnosis. Methods: We reviewed the final diagnosis of all patients prospectively registered in the Sant Pau-MND register from 1 January 2004 to 31 December 2015. A detailed clinical evaluation and a clinically-guided electrophysiological study were performed at first evaluation. Results: Twenty of 314 (6.4%) patients included were re-diagnosed as having a condition other than ALS, in 18 cases already at first evaluation. An alternative specific diagnosis was identified in 17 of those 20, consisting of a wide range of conditions. The main finding leading to an alternative diagnosis was the result of the electrophysiological study. Fifty per cent did not fulfil the El Escorial revised criteria (EECr) for ALS. The most common clinical phenotype at onset in patients with ALS mimic syndromes was progressive muscular atrophy (PMA). Conclusions: Misdiagnosing ALS is still a common problem. Early identification of ALS mimic syndromes is possible based on atypical clinical features and a clinically-guided electrophysiological study. Patients should be attended in specialised centres. The application of EECr helps to identify ALS misdiagnoses. © 2017 World Federation of Neurology on behalf of the Research Group on Motor Neuron Diseases.

The scientific scenario of amyotrophic lateral sclerosis (ALS) has dramatically changed since TDP-43 aggregates were discovered in 2006 as the main component of the neuronal inclusions seen in the disease, and more recently, when the implication of C9ORF72 expansion in familial and sporadic cases of ALS and frontotemporal dementia was confirmed. These discoveries have enlarged an extense list of genes implicated in different cellular processes such as RNA processing or autophagia among others and have broaden the putative molecular targets of the disease. Some of ALS-related genes such as TARDBP or SOD1 among others have important roles in the regulation of glucose and fatty acids metabolism, so that an impairment of fatty acids (FA) consumption and ketogenic deficits during exercise in ALS patients would connect the physiopathology with some of the more intriguing epidemiological traits of the disease. The current understanding of ALS as part of a continuum with other neurodegenerative diseases and a crossroads between genetic, neurometabolic and environmental factors represent a fascinating model of interaction that could be translated to other neurodegenerative diseases. In this review we summarize the most relevant data obtained in the ten last years and the key lines for future research in ALS. (C) 2016 Elsevier Ltd. All rights reserved.

Background and purposeMyasthenia gravis (MG) may become life-threatening if patients have respiratory insufficiency or dysphagia. This study aimed to determine the incidence, demographic characteristics, risk factors, response to treatment and outcome of these life-threatening events (LTEs) in a recent, population-based sample of MG patients. MethodsA retrospective analysis of MG patients who presented with an LTE between 2000 and 2013 was performed. Participants were identified from a neuromuscular diseases registry in Spain that includes 648 patients with MG (NMD-ES). ResultsSixty-two (9.56%) patients had an LTE. Thirty-two were classified as class V according to the MG Foundation of America, and 30 as class IVB. Fifty per cent were previously diagnosed with MG and median duration of the disease before the LTE was 24months (3-406). The most common related factor was infection (n=18). All patients received intravenous human immunoglobulin; 11 had a second infusion and six had plasma exchange. Median time to feeding tube removal was 13days (1-434). Median time to weaning from ventilation was 12days (3-176), and it was significantly shorter in late onset MG (50years) (P=0.019). LTEs improved

We investigated the molecular mechanisms involved in the pathogenesis of three inflammatory myopathies, dermatomyositis (DM), polymyositis (PM) and inclusion body myositis (IBM). We performed microarray experiments dagger using microdissected pathological muscle fibres from 15 patients with these disorders and five controls. Differentially expressed candidate genes were validated by immunohistochemistry on muscle biopsies, and the altered pathways were analysed in human myotube cultures. Up-regulation of genes involved in viral and nucleic acid recognition were found in the three myopathies but not in controls. In DM, retinoic acid-inducible gene 1 (RIG-I, DDX58) and the novel antiviral factor DDX60, which promotes RIG-I-mediated signalling, were significantly up-regulated, followed by IFIH1 (MDA5) and TLR3. Immunohistochemistry confirmed over-expression of RIG-I in pathological muscle fibres in 5/5 DM, 0/5 PM and 0/5 IBM patients, and in 0/5 controls. Stimulation of human myotubes with a ligand of RIG-I produced a significant secretion of interferon- (IFN; p < 0.05) and up-regulation of class I MHC, RIG-I and TLR3 (p < 0.05) by IFN-dependent and TLR3-independent mechanisms. RIG-I-mediated innate immunity, triggered by a viral or damage signal, plays a significant role in the pathogenesis of DM, but not in that of PM or IBM. Copyright (c) 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd

Thyrotoxic periodic paralysis (TPP) is a rare complication of hyperthyroidism characterized by episodes of weakness. Although TPP has been described in patients all over the world, it is especially frequent in Asiatic patients. Recently, two genomewide association studies have found a susceptibility locus on chromosome 17q24.3 near the KCNJ2 gene, which is responsible for another cause of periodic paralysis, the Andersen-Tawil syndrome (ATS). We report the first patient diagnosed with ATS with a de novo c. G899C mutation in the KCNJ2 gene in 2010 who developed an autoimmune hyperthyroidism and TPP in 2013. At the time of the ATS diagnosis other causes of periodic paralysis, including thyroid dysfunction, were ruled out. The condition of the patient, who had mild episodes of proximal weakness at follow-up, deteriorated dramatically in 2013, presenting continuous episodes of severe generalized weakness associated with low levels of potassium requiring frequent admissions to the hospital. After a few months, he also presented signs of hyperthyroidism, and a diagnosis of Grave's disease was made. In our opinion, this case clearly demonstrates that a dysfunction of the Kir2.1 potassium channel encoded by the KCNJ2 gene is a risk factor to develop TPP, and can be a useful tool to identify patients at risk in daily clinics.

Objective Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a frequent autoimmune neuropathy with a heterogeneous clinical spectrum. Clinical and experimental evidence suggests that autoantibodies may be involved in its pathogenesis, but the target antigens are unknown. Axoglial junction proteins have been proposed as candidate antigens. We examined the reactivity of CIDP patients' sera against neuronal antigens and used immunoprecipitation for antigen unraveling. Methods Primary cultures of hippocampal neurons were used to select patients' sera that showed robust reactivity with the cell surface of neurons. The identity of the antigens was established by immunoprecipitation and mass spectrometry, and subsequently confirmed with cell-based assays, immunohistochemistry with teased rat sciatic nerve, and immunoabsorption experiments. Results Four of 46 sera from patients with CIDP reacted strongly against hippocampal neurons (8.6%) and paranodal structures on peripheral nerve. Two patients' sera precipitated contactin-1 (CNTN1), and 1 precipitated both CNTN1 and contactin-associated protein 1 (CASPR1). Reactivity against CNTN1 was confirmed in 2 cases, whereas the third reacted only when CNTN1 and CASPR1 were cotransfected. No other CIDP patient or any of the 104 controls with other neurological diseases tested positive. All 3 patients shared common clinical features, including advanced age, predominantly motor involvement, aggressive symptom onset, early axonal involvement, and poor response to intravenous immunoglobulin. Interpretation Antibodies against the CNTN1/CASPR1 complex occur in a subset of patients with CIDP who share common clinical features. The finding of this biomarker may help to explain the symptoms of these patients and the heterogeneous response to therapy in CIDP. ANN NEUROL 2013;73:370380

Our objective was to determine the incidence and clinical-epidemiological characteristics of an ALS cohort patient in Catalonia (Spain). We conducted a population based registry for a three-year period (1999-2001) in Catalonia (6,361,365 inhabitants) using several sources of information. The original El Escorial diagnostic criteria (1994) for ALS were applied for the classification of patients. New cases diagnosed between 1 January 1999 and 31 December 2001 were 215 (118 males and 97 females), with an annual crude incidence rate of 1.4/100,000 (95% CI 1.3-1.8). This rate showed a peak age between 75 and 79 years. The incidence rate was 1.6 (95% CI 1.5-2.2) in males and 1.2 (95% CI 1.1-1.7) in females. Prevalence at the end of the period was 5.4/100,000 of the total population. Median age at onset was 64.3 years. Onset of symptoms was bulbar or generalized in 38% of cases. Mean disease duration at diagnosis was 11.0 months. Median time of survival from onset was 30.8 months. In conclusion, ALS incidence in Catalonia is within the range of other countries across Europe with different geographic, environmental and socioeconomic situations. However, as in other studies conducted in the Mediterranean area, Catalonia incidence is in the lower range of rates in Europe.

A hexanucleotide repeat expansion in chromosome 9 open reading frame 72 (C9orf72) can cause amyotrophic lateral sclerosis (ALS) and/or frontotemporal dementia (FTD). We assessed its frequency in 781 sporadic ALS (sALS) and 155 familial ALS (fALS) cases, and in 248 Spanish controls. We tested the presence of the reported founder haplotype among mutation carriers and in 171 Ceph Europeans from Utah (CEU), 170 Yoruba Africans, 81 Han Chinese, and 85 Japanese subjects. The C9orf72 expansion was present in 27.1% of fALS and 3.2% of sALS. Mutation carriers showed lower age at onset (P = 0.04), shorter survival (P = 0.02), greater co-occurrence of FTD (P = 8.2 x 10(-5)), and more family history of ALS (P = 1.4 x 10(-20)), than noncarriers. No association between alleles within the normal range and the risk of ALS was found (P = 0.12). All 61 of the mutation carriers were tested and a patient carrying 28 hexanucleotide repeats presented with the founder haplotype. This haplotype was found in 5.6% Yoruba Africans, 8.9% CEU, 3.9% Japanese, and 1.6% Han Chinese chromosomes. Hum Mutat 34:79-82, 2013. (C) 2012 Wiley Periodicals, Inc.

Previous studies have suggested a lower incidence of ALS in people of African origin. We used a population based register in an urban setting from inner city London postcodes where there is a large population of people of African ancestry to compare the frequency of ALS in people of European and African origin. Population statistics stratified by age, gender and ethnicity were obtained from the 2001 census. Incidence and prevalence were calculated in each ethnic group. Results showed that in a population of 683,194, of which 22% were of African ancestry, 88 individuals with ALS were identified over a seven-year period, including 14 people with African ancestry. The adjusted incidence in people of African ancestry was 1.35 per 100,000 person-years (95% CI 0.722.3) and in those of European ancestry 1.97 per 100,000 person-years (95% CI 1.552.48). In conclusion, in this small population based study we could not detect a difference in rates of ALS between people of African ancestry and those of European ancestry. © 2012 Informa Healthcare.

Dysferlinopathies are a heterogenous group of autosomal recessive inherited muscular dystrophies caused by mutations in DYSF gene. Dysferlin is expressed mainly in skeletal muscle and in monocytes and patients display a severe reduction or absence of protein in both tissues. Vitamin D3 promotes differentiation of the promyelocytic leukemia HL60 cells. We analyzed the effect of vitamin D3 on dysferlin expression in vitro using HL60 cells, monocytes and myotubes from controls and carriers of a single mutation in DYSF. We also performed an observational study with oral vitamin D3 in a cohort of 21 carriers. Fifteen subjects were treated for 1 year and dysferlin expression in monocytes was analysed before and after treatment. Treatment with vitamin D3 increased expression of dysferlin in vitro. The effect of vitamin D3 was mediated by both a nongenomic pathway through MEK/ERK and a genomic pathway involving binding of vitamin D3 receptor to the dysferlin promoter. Carriers treated with vitamin D3 had significantly increased expression of dysferlin in monocytes compared with nontreated carriers (P < 0.05). These findings will have important therapeutic implications since a combination of different molecular strategies together with vitamin D3 uptake could increase dysferlin expression to nonpathological protein levels.

Peripheral nerve disorders are a common complication in HIV patients, reaching 15% of them. Several patterns and aetiologies have been described, being lumbosacral poliradiculoneuropathy one of them. We describe an HIV-1-infected patient who developed lumbosacral poliradiculoneuropathy caused by Human herpesvirus 2 and review the literature about this uncommon condition.

Background Reactivity against terminal NeuNAc(alpha 2-3) Gal, common to several gangliosides such as GD1a, GT1b and GM3, has rarely been reported. The authors recently described a patient with a clinical picture of acute relapsing sensory ataxic neuropathy and bulbar involvement in whom they demonstrated concomitant reactivity against NeuNAc(alpha 2-3) Gal and disialosyl epitopes. The authors suggested a correlation between NeuNAc(alpha 2-3) Gal reactivity and bulbar involvement. Aim To determine the frequency of reactivity against terminal NeuNAc(alpha 2-3) Gal in acute and chronic immune-mediated disorders, and its possible correlation with bulbar involvement. Methods The authors retrospectively reviewed reactivity in the serum of more than 3000 consecutive patients with acute and chronic disorders in which antiganglioside antibodies were studied. The authors selected those patients who were simultaneously positive, by ELISA or thin-layer chromatography, for IgG or IgM antibodies anti-GM3, GD1a and GT1b, and reviewed their clinical features. Results Reactivity against NeuNAc(alpha 2-3) Gal, shared by GM3, GD1a and GT1b gangliosides, was detected in 10 patients: isolated in one patient, and concomitant with reactivity against other gangliosides in the remaining patients. Reactivity against NeuNAc(alpha 2-3) Gal was frequently associated (8/10) with symptoms suggestive of bulbar involvement, such as dysphagia, dysarthria or dysphonia. Severe respiratory failure requiring mechanical ventilation was observed in four patients. Conclusions Reactivity against the NeuNAc(alpha 2-3) Gal epitope is rare and is generally found in association with reactivity against the disialosyl epitope. It can be detected in patients with acute or chronic disorders and could be a serological marker of clinical bulbar involvement and, to a lesser extent, associated with the development of severe respiratory failure.

Advances in the treatment of myasthenia gravis (MG) have reduced mortality rates due to the disease and improved patients' quality of life. Nowadays, attending neurologists can choose among different treatment strategies for MG patients. An exhaustive revision of published data on the efficacy of the different therapeutic options for MG indicates that there are insufficient evidence-based results. However, recommendations based on expert opinion can be provided. Thymectomy is indicated in all patients with a thymoma or for generalized acetylcholine receptor-seropositive patients aged 18 - 55 years. Steroids are the most widely used immunosuppressive drug for MG. They are recommended as the first-line drug in all patients with generalized MG without response to thymectomy, or in those patients who do not fulfill criteria for the surgery. The selection of second-line drugs may vary between protocols. We recommend to start with azathioprine if insufficient remission is achieved with steroids, followed by ciclosporin, mycophenolate and others. We use rituximab or cyclophosphamide only in severely drug-resistant patients. Finally, we recommend intravenous immunoglobulins or plasma exchange in MG crisis, or for unstable patients before thymectomy or in clinical exacerbations.

Introduction: The objective of this retrospective study was to describe the short- and long-term patterns of IVIg use, safety, and response to treatment in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). Methods: Response to therapy was defined as an improvement of 1 point on the modified Rankin score at short- and mid-term visits. Patient status at long term was classified as remission, stability, or non-responder. Results: Eighty-six patients were included; 60.5% responded at short term and 54.6% at mid-term. At long term, 25.6% of patients were in remission, 65.1% were stable, and 9.3% were non-responders. The only variable associated with remission was a better response during the first 6 months of follow-up. Conclusions: A significant percentage of patients did not require any additional drugs in the long term. This suggests that treatment effect or disease outcome may be stable over time, and treatment regimens should therefore be individualized to avoid overtreatment. Muscle Nerve48: 870-876, 2013