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OBJECTIVE: The aim of this study was to provide an overview of the clinical phenotypes associated with 4 SMN2 copies. METHODS: Clinical phenotypes were analyzed in all the patients with 4 SMN2 copies as part of a nationwide effort including all the Italian pediatric and adult reference centers for spinal muscular atrophy (SMA). RESULTS: The cohort includes 169 patients (102 men and 67 women) with confirmed 4 SMN2 copies (mean age at last follow-up = 36.9 ± 19 years). Six of the 169 patients were presymptomatic, 8 were classified as type II, 145 as type III (38 type IIIA and 107 type IIIB), and 8 as type IV. The remaining 2 patients were asymptomatic adults identified because of a familial case. The cross-sectional functional data showed a reduction of scores with increasing age. Over 35% of the type III and 25% of the type IV lost ambulation (mean age = 26.8 years ± 16.3 SD). The risk of loss of ambulation was significantly associated with SMA type (p < 0.0001), with patients with IIIB and IV less likely to lose ambulation compared to type IIIA. There was an overall gender effect with a smaller number of women and a lower risk for women to lose ambulation. This was significant in the adult (p = 0.009) but not in the pediatric cohort (p = 0.43). INTERPRETATION: Our results expand the existing literature on natural history of 4 SMN2 copies confirming the variability of phenotypes in untreated patients, ranging from type II to type IV and an overall reduction of functional scores with increasing age. ANN NEUROL 2023;94:1126-1135.
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Atrofia Muscular Espinal , Masculino , Adulto , Niño , Humanos , Femenino , Adolescente , Adulto Joven , Persona de Mediana Edad , Estudios Transversales , Atrofia Muscular Espinal/diagnóstico , Atrofia Muscular Espinal/genética , Fenotipo , Caminata , Proteína 1 para la Supervivencia de la Neurona Motora/genética , Proteína 2 para la Supervivencia de la Neurona Motora/genéticaRESUMEN
INTRODUCTION/AIMS: MScanFit MUNE (MScanFit) is a novel tool to derive motor unit number estimates (MUNEs) from compound muscle action potential (CMAP) scans. Few studies have explored its utility in 5q spinal muscular atrophy (SMA5q) patients, assessing only the abductor pollicis brevis (APB) muscle. We aimed to assess different distal muscles in pediatric and adult SMA5q patients, further evaluating clinical-electrophysiological correlations. METHODS: We analyzed MScanFit parameters reflecting the extent of denervation (MUNE; N50) and parameters of collateral reinnervation in APB, abductor digiti minimi (ADM), and tibialis anterior (TA) muscles. SMA patients were clinically evaluated using standardized motor function clinical scales, including the Hammersmith Functional Motor Scale - Expanded and the Revised Upper Limb Module. RESULTS: A total of 23 SMA5q (9 SMA type 2 and 14 SMA type 3) and 12 age-matched healthy controls (HCs) were enrolled. SMA patients showed lower MUNE and N50 values and higher parameters of collateral sprouting in all muscles compared to HC (p < .001). SMA type 2 patients demonstrated lower MUNE and higher collateral reinnervation values in APB and TA compared to SMA type 3 (p < .05). Walker patients showed higher values of MUNE and N50, and lower parameters of reinnervation in all muscles compared to sitters (p < .05). MScanFit parameters showed strong correlations (Rho-values ranging from .72 to .83) with clinical measurements. MUNE values were abnormal in muscles that were not clinically affected. DISCUSSION: MScanFit parameters showed promise as an outcome measure. Further studies, particularly longitudinal ones, are needed to evaluate MScanFit in measuring response to treatments.
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Potenciales de Acción , Neuronas Motoras , Músculo Esquelético , Atrofia Muscular Espinal , Humanos , Femenino , Masculino , Atrofia Muscular Espinal/fisiopatología , Adulto , Músculo Esquelético/fisiopatología , Potenciales de Acción/fisiología , Niño , Adolescente , Neuronas Motoras/fisiología , Adulto Joven , Electromiografía , Persona de Mediana Edad , Atrofias Musculares Espinales de la Infancia/fisiopatología , Reclutamiento Neurofisiológico/fisiologíaRESUMEN
INTRODUCTION/AIMS: Fatigue (subjective perception) and fatigability (objective motor performance worsening) are relevant aspects of disability in individuals with spinal muscular atrophy (SMA). The effect of nusinersen on fatigability in SMA patients has been investigated with conflicting results. We aimed to evaluate this in adult with SMA3. METHODS: We conducted a multicenter retrospective cohort study, including adult ambulant patients with SMA3, data available on 6-minute walk test (6MWT) and Hammersmith Functional Motor Scale-Expanded (HFMSE) at baseline and at least at 6 months of treatment with nusinersen. We investigated fatigability, estimated as 10% or higher decrease in walked distance between the first and sixth minute of the 6MWT, at baseline and over the 14-month follow-up. RESULTS: Forty-eight patients (56% females) were included. The 6MWT improved after 6, 10, and 14 months of treatment (p < 0.05). Of the 27 patients who completed the entire follow-up, 37% improved (6MWT distance increase ≥30 m), 48.2% remained stable, and 14.8% worsened (6MWT distance decline ≥30 m). Fatigability was found at baseline in 26/38 (68%) patients and confirmed at subsequent time points (p < 0.05) without any significant change over the treatment period. There was no correlation between fatigability and SMN2 copy number, sex, age at disease onset, age at baseline, nor with 6MWT total distance and baseline HFMSE score. DISCUSSION: Fatigability was detected at baseline in approximately 2/3 of SMA3 walker patients, without any correlation with clinical features, included motor performance. No effect on fatigability was observed during the 14-month treatment period with nusinersen.
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INTRODUCTION: Intraspinal cerebrospinal fluid (CSF) collection has been reported as a rare cause of lower motor neuron (LMN) disorder. We report a case of bibrachial diplegia associated with intraspinal CSF collection and perform a systematic literature review. PATIENT AND METHODS: A 52-year-old man developed a bibrachial amyotrophy over 6 years, confirmed by the presence of cervical subacute neurogenic changes at electromyography (EMG). Brain magnetic resonance imaging (MRI) revealed cerebral siderosis, while spine MRI showed a ventral longitudinal intraspinal fluid collection (VLISFC) from C2 to L2. No CSF leakage was localized at myelography; a conservative treatment was chosen. We searched for all published cases until 30th April 2023 and extrapolated data of 44 patients reported in 27 publications. RESULTS: We observed a male predominance, a younger disease onset compared to amyotrophic lateral sclerosis, and a quite long disease duration, highlighting a slow disease progression. LMN signs were more frequently bilateral, mostly involving C5-C6 myotomes. Around 61% of patients presented additional symptoms, but only three referred to a history of headache. Accordingly, CSF opening pressure was mostly normal. Spinal MRI revealed the presence of VLISFC and in some cases myelomalacia. EMG patterns displayed both chronic and subacute neurogenic change in the cervical region. The disease course mainly depended on the treatment choice, which was mostly represented by a surgical approach when a specific dural defect was detected by imaging. CONCLUSION: Bibrachial diplegia due to VLISFC can be a treatable cause of focal amyotrophy and presents some clinical and radiological "red flags" which cannot be missed by a clinical neurologist.
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Hipotensión Intracraneal , Enfermedad de la Neurona Motora , Enfermedades de la Médula Espinal , Humanos , Masculino , Persona de Mediana Edad , Femenino , Pérdida de Líquido Cefalorraquídeo/complicaciones , Imagen por Resonancia Magnética , Enfermedad de la Neurona Motora/complicaciones , Mielografía , Hipotensión Intracraneal/etiologíaRESUMEN
BACKGROUND: Phosphorylated-tau181 (p-tau181), a specific marker of Alzheimer's disease (AD) pathology, was found elevated in plasma but not in cerebrospinal fluid (CSF) of patients with amyotrophic lateral sclerosis (ALS). We expanded these findings in a larger patient cohort, exploring clinical/electrophysiological associations, prognostic value and longitudinal trajectories of the biomarker. METHODS: We obtained baseline plasma samples from 148 ALS, 12 spinal muscular atrophy (SMA), and 88 AD patients, and 60 healthy controls. Baseline CSF and longitudinal plasma samples were from 130 and 39 patients with ALS. CSF AD markers were measured with the Lumipulse platform, and plasma p-tau181 with SiMoA. RESULTS: Patients with ALS showed higher plasma p-tau181 levels than controls (p<0.001) and lower than AD participants (p=0.02). SMA patients had higher levels than controls (p=0.03). In patients with ALS, CSF p-tau and plasma p-tau181 did not correlate (p=0.37). Plasma p-tau181 significantly increased with the number of regions showing clinical/neurophysiological lower motor neurons (LMN) signs (p=0.007) and correlated with the degree of denervation in the lumbosacral area (r=0.51, p<0.0001). Plasma p-tau181 levels were higher in classic and LMN-predominant than in bulbar phenotype (p=0.004 and p=0.006). Multivariate Cox regression confirmed plasma p-tau181 as an independent prognostic factor in ALS (HR 1.90, 95% CI 1.25 to 2.90, p=0.003). Longitudinal analysis showed a significant rise in plasma p-tau181 values over time, especially in fast progressors. CONCLUSIONS: Plasma p-tau181 is elevated in patients with ALS, independently from CSF levels, and is firmly associated with LMN dysfunction. The finding indicates that p-tau181 of putative peripheral origin might represent a confounding factor in using plasma p-tau181 for AD pathology screening, which deserves further investigation.
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Enfermedad de Alzheimer , Esclerosis Amiotrófica Lateral , Humanos , Enfermedad de Alzheimer/diagnóstico , Proteínas tau/líquido cefalorraquídeo , Pronóstico , Biomarcadores/líquido cefalorraquídeo , Péptidos beta-Amiloides/líquido cefalorraquídeoRESUMEN
Recent studies reported increased plasma glial acidic fibrillary protein (GFAP) levels in amyotrophic lateral sclerosis (ALS) patients compared to controls. We expanded these findings in a larger cohort, including 156 ALS patients and 48 controls, and investigated the associations of plasma GFAP with clinical variables and other biofluid biomarkers. Plasma GFAP and Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers were assessed by the single molecule array and the Lumipulse platforms, respectively. In ALS patients, plasma GFAP was higher than in controls (p < 0.001) and associated with measures of cognitive decline. Twenty ALS patients (12.8%) showed a positive amyloid status (A+), of which nine also exhibited tau pathology (A+T+, namely ALS-AD). ALS-AD patients showed higher plasma GFAP than A- ALS participants (p < 0.001) and controls (p < 0.001), whereas the comparison between A- ALS and controls missed statistical significance (p = 0.07). Plasma GFAP distinguished ALS-AD subjects more accurately (area under the curve (AUC) 0.932 ± 0.027) than plasma p-tau181 (AUC 0.692 ± 0.058, p < 0.0001) and plasma neurofilament light chain protein (AUC, 0.548 ± 0.088, p < 0.0001). Cognitive measures differed between ALS-AD and other ALS patients. AD co-pathology deeply affects plasma GFAP values in ALS patients. Plasma GFAP is an accurate biomarker for identifying AD co-pathology in ALS, which can influence the cognitive phenotype.
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BACKGROUND: Natural history of spinal muscular atrophy (SMA) in adult age has not been fully elucidated yet, including factors predicting disease progression and response to treatments. Aim of this retrospective, cross-sectional study, is to investigate motor function across different ages, disease patterns and gender in adult SMA untreated patients. METHODS: Inclusion criteria were as follows: (1) clinical and molecular diagnosis of SMA2, SMA3 or SMA4 and (2) clinical assessments performed in adult age (>18 years). RESULTS: We included 64 (38.8%) females and 101 (61.2%) males (p=0.0025), among which 21 (12.7%) SMA2, 141 (85.5%) SMA3 and 3 (1.8%) SMA4. Ratio of sitters/walkers within the SMA3 subgroup was significantly (p=0.016) higher in males (46/38) than in females (19/38). Median age at onset was significantly (p=0.0071) earlier in females (3 years; range 0-16) than in males (4 years; range 0.3-28), especially in patients carrying 4 SMN2 copies. Median Hammersmith Functional Rating Scale Expanded scores were significantly (p=0.0040) lower in males (16, range 0-64) than in females (40, range 0-62); median revised upper limb module scores were not significantly (p=0.059) different between males (24, 0-38) and females (33, range 0-38), although a trend towards worse performance in males was observed. In SMA3 patients carrying three or four SMN2 copies, an effect of female sex in prolonging ambulation was statistically significant (p=0.034). CONCLUSIONS: Our data showed a relevant gender effect on SMA motor function with higher disease severity in males especially in the young adult age and in SMA3 patients.
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Atrofia Muscular Espinal , Atrofias Musculares Espinales de la Infancia , Adulto Joven , Masculino , Humanos , Femenino , Preescolar , Adolescente , Atrofias Musculares Espinales de la Infancia/epidemiología , Atrofias Musculares Espinales de la Infancia/genética , Atrofias Musculares Espinales de la Infancia/tratamiento farmacológico , Estudios Transversales , Estudios Retrospectivos , Atrofia Muscular Espinal/epidemiología , Atrofia Muscular Espinal/genética , Progresión de la EnfermedadRESUMEN
OBJECTIVES: Autoimmune encephalitis due to antibodies against neuronal surface antigens (NSA-Ab) frequently presents with cognitive impairment, often as the first and prevalent manifestation, but few studies have systematically assessed the frequency of NSA-Ab in consecutive patients with established neurodegenerative disorders. METHODS: We studied sera of 93 patients (41F, 52 M), aged 69.2 ± 9.4 years, with neurodegenerative conditions, and of 50 population controls aged over 60 years. Specific NSA-Abs were investigated by antigen-specific cell-based assays (CBAs). After testing, we evaluated the association between the NSA-Abs and clinical, CSF and radiological features. RESULTS: The patients included 13/93 (13.8%) who had specific antibodies to neuronal surface antigens: 6 GlyR, 3 GABAAR (1 also positive for AMPAR), 2 LGI1, 1 CASPR2 and 1 GABABR. One of the 50 controls (2%) was positive for NMDAR antibody and the others were negative on all tests (P = 0.020). No difference was observed in antibody frequency between patients presenting with parkinsonism and those presenting with dementia (P = 0.55); however, NSA-Ab were more frequent in those with unclassified forms of dementia (5/13, 38.5%) than in those with unclassified parkinsonism (2/9, 22.2%) or with classified forms of dementia (4/43, 9.3%) or parkinsonism (2/28, 7.1%) (P = 0.03). A logistic regression analysis demonstrated that an unclassified diagnosis (P = 0.02) and an irregular progression (P = 0.024) were predictors of seropositive status. CONCLUSIONS: NSA-Abs are relatively frequent in patients with neurodegenerative disorders, particularly in those with an irregular disease progression of atypical clinical features, inconsistent with a recognized diagnosis. The significance of these antibodies and their possible primary or secondary roles need to be investigated in prospective studies.
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Encefalitis , Enfermedad de Hashimoto , Enfermedades Neurodegenerativas , Antígenos de Superficie , Autoanticuerpos , Humanos , Enfermedades Neurodegenerativas/diagnóstico , Estudios ProspectivosRESUMEN
BACKGROUND AND PURPOSE: The aim of this study was to evaluate brain metabolic correlates of apathy in amyotrophic lateral sclerosis (ALS). METHODS: A total of 165 ALS patients underwent 18 F-2-fluoro-2-deoxy-D-glucose positron emission tomography (18 F-FDG-PET) and Frontal Systems Behaviour Scale (FrSBe) evaluation. FrSBe provides "before" and "after" apathy subscores, referring to premorbid and morbid conditions. "After" apathy subscore and "before-after" gap, i.e. the difference between "before" and "after" subscores, were regressed against whole-brain metabolism. Among patients with a pathological "after" apathy subscore (i.e., ≥65), we compared patients with "before" apathy subscores ≥65 and <65, and patients with "before-after" gaps of <22 and ≥22. RESULTS: In the whole sample, the "after" apathy subscore negatively correlated with metabolism in the dorsolateral prefrontal cortex (DLPFC), dorsomedial prefrontal cortex (DMPFC), ventrolateral prefrontal cortex (VLPFC), premotor cortex (PMC) and anterior cingulate cortex (ACC), and insula bilaterally. A positive correlation was found in the cerebellum and pons. The "before-after" gap negatively correlated with metabolism in bilateral DLPFC, DMPFC and PMC, and left VLPFC and ACC, and positively correlated with cerebellar and pontine clusters. Among patients with an "after" apathy subscore ≥65, we found no difference between those with "before" apathy subscores ≥65 and <65. Patients with a "before-after" gap ≥22, compared to patients with a gap <22, showed relative hypometabolism in bilateral DLPFC and DMPFC, and left ACC and PMC, and relative cerebellar and pontine hypermetabolism. CONCLUSION: No studies on brain 18 F-2-fluoro-2-deoxy-D-glucose positron emission tomography correlates of apathy have been performed in ALS. We found that FrSBe "after" apathy subscore correlated with metabolic changes in brain regions known as neuroanatomical correlates of apathy. Furthermore, our findings support the relevance of the gap between premorbid and morbid conditions to detect behavioural changes due to the neurodegenerative process underlying ALS.
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Esclerosis Amiotrófica Lateral , Apatía , Esclerosis Amiotrófica Lateral/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Humanos , Tomografía de Emisión de PositronesRESUMEN
OBJECTIVE: To retrospectively investigate safety and efficacy of nusinersen in a large cohort of adult Italian patients with spinal muscular atrophy (SMA). METHODS: Inclusion criteria were: (1) clinical and molecular diagnosis of SMA2 or SMA3; (2) nusinersen treatment started in adult age (>18 years); (3) clinical data available at least at baseline (T0-beginning of treatment) and 6 months (T6). RESULTS: We included 116 patients (13 SMA2 and 103 SMA3) with median age at first administration of 34 years (range 18-72). The Hammersmith Functional Rating Scale Expanded (HFMSE) in patients with SMA3 increased significantly from baseline to T6 (median change +1 point, p<0.0001), T10 (+2, p<0.0001) and T14 (+3, p<0.0001). HFMSE changes were independently significant in SMA3 sitter and walker subgroups. The Revised Upper Limb Module (RULM) in SMA3 significantly improved between T0 and T14 (median +0.5, p=0.012), with most of the benefit observed in sitters (+2, p=0.018). Conversely, patients with SMA2 had no significant changes of median HFMSE and RULM between T0 and the following time points, although a trend for improvement of RULM was observed in those with some residual baseline function. The rate of patients showing clinically meaningful improvements (as defined during clinical trials) increased from 53% to 69% from T6 to T14. CONCLUSIONS: Our data provide further evidence of nusinersen safety and efficacy in adult SMA2 and SMA3, with the latter appearing to be cumulative over time. In patients with extremely advanced disease, effects on residual motor function are less clear.
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Oligonucleótidos Antisentido/uso terapéutico , Oligonucleótidos/uso terapéutico , Atrofias Musculares Espinales de la Infancia/tratamiento farmacológico , Adolescente , Adulto , Edad de Inicio , Anciano , Estudios de Cohortes , Femenino , Volumen Espiratorio Forzado , Estado Funcional , Humanos , Inyecciones Espinales , Italia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sedestación , Atrofias Musculares Espinales de la Infancia/fisiopatología , Resultado del Tratamiento , Capacidad Vital , Prueba de Paso , Caminata , Adulto JovenRESUMEN
INTRODUCTION: Myasthenia gravis (MG) can be aggravated by several classes of drugs, including antibiotics. Penicillins are considered safe drugs for the management of infectious disease in patients with MG. However, a few cases of MG exacerbations after penicillin treatment have been reported in literature. CASE REPORTS: We report six patients with MG developing acute worsening of symptoms after amoxicillin or amoxicillin/clavulanate treatment. In most of the cases, symptoms started in a few days after antibiotic administration. In all cases, we observed a worsening of the Myasthenia Gravis Foundation of America (MGFA) clinical classification. Most patients required a therapeutic intervention with dosage increase of the previous therapy or the introduction of new drugs for MG. All patients had a full recovery to baseline neurological conditions within 1-2 months. CONCLUSIONS: We concluded that patients receiving amoxicillin should be closely monitored for possible acute relapse.
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Amoxicilina , Miastenia Gravis , Amoxicilina/efectos adversos , Antibacterianos/efectos adversos , Enfermedad Crónica , Humanos , Miastenia Gravis/inducido químicamente , Miastenia Gravis/tratamiento farmacológico , Recurrencia Local de NeoplasiaRESUMEN
INTRODUCTION: Neurological manifestations can occur during coronavirus disease 19 (COVID-19). Several pathogenic mechanisms have been hypothesized, without conclusive results. In this study, we evaluated the most frequent neurological symptoms in a cohort of hospitalized COVID-19 patients, and also investigated the possible relationship between plasmatic inflammatory indices and olfactory disorders (ODs) and between muscle pain and creatine kinase (CK). METHODS: We consecutively enrolled hospitalized COVID-19 patients. A structured questionnaire concerning typical and neurological symptoms, focusing on headache, dizziness, ODs, taste disorders (TDs), and muscle pain, was administrated by telephone interviews. RESULTS: Common neurological symptoms were reported in the early phase of the disease, with a median onset ranging from 1 to 3 days. Headache showed tension-type features and was more frequently associated with a history of headache. Patients with ODs less frequently needed oxygen therapy. Inflammatory indices did not significantly differ between patients with and without ODs. Muscle pain did not show any association with CK level but was more frequently associated with arthralgia and headache. CONCLUSION: In our cohort, ODs were an early symptom of COVID-19, more frequently reported by patients with milder forms of disease. Headache in association with arthralgia and muscle pain seems to reflect the common symptoms of the flu-like syndrome, and not COVID-19 infection-specific.
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Infecciones por Coronavirus/complicaciones , Cefalea/virología , Mialgia/virología , Trastornos del Olfato/virología , Neumonía Viral/complicaciones , Trastornos del Gusto/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19 , Creatina Quinasa/sangre , Femenino , Cefalea/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Mialgia/epidemiología , Trastornos del Olfato/epidemiología , Pandemias , Prevalencia , Encuestas y Cuestionarios , Trastornos del Gusto/epidemiología , Adulto JovenRESUMEN
BACKGROUND: Uric acid (UA) is a strong natural scavenger of reactive oxygen and nitrogen species, with evidence of possible use in the treatment of animal models of multiple sclerosis (MS). Consequently, serum UA has gained much attention as a possible biomarker of MS. We aim to investigate differences in serum UA levels between MS subjects and controls and evaluate possible relationships of UA with MS clinical features. METHODS: We recruited relapsing-remitting and secondary progressive MS subjects and healthy controls and measured their serum UA levels. We excluded subjects presenting concomitant conditions affecting UA levels. RESULTS: MS subjects (n=362) and controls (n=181) were recruited by propensity score matching (PSM). Statistical analyses were corrected for age, gender, and renal function. MS subjects presented significantly lower serum UA levels than controls (analysis of variance, p=0.014, adjusted r2=0.3036). Linear regression analysis showed a relationship between UA levels and disease duration (p<0.001, adjusted r2=0.3158, coefficient -0.00039), time from diagnosis (p<0.001, adjusted r2=0.3100, coefficient -0.0012), and Expanded Disability Status Scale (EDSS) (p<0.001, adjusted r2=0.3230, coefficient -0.1). CONCLUSIONS: Our findings support the importance of serum UA as a biomarker of MS disability and progression. Further studies with longitudinal design should be specifically designed to evaluate the importance of UA in the different stages of MS and in relation to distinct therapeutic strategies.
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Esclerosis Múltiple/sangre , Ácido Úrico/sangre , Adolescente , Adulto , Anciano , Biomarcadores/sangre , Personas con Discapacidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
Primary lateral sclerosis (PLS) is a rare neurodegenerative disorder which causes the selective deterioration of the upper motor neurons (UMNs), sparing the lower motor neuron (LMN) system. The clinical course is defined by a progressive motor disability due to muscle spasticity which typically involves lower extremities and bulbar muscles. Although classically considered a sporadic disease, some familiar cases and possible causative genes have been reported. Despite it having been recognized as a rare but distinct entity, whether it actually represents an extreme end of the motor neuron diseases continuum is still an open issue. The main knowledge gap is the lack of specific biomarkers to improve the clinical diagnostic accuracy. Indeed, the diagnostic imprecision, together with some uncertainty about overlap with UMN-predominant ALS and Hereditary Spastic Paraplegia (HSP), has become an obstacle to the development of specific therapeutic trials. In this study, we provided a comprehensive analysis of the existing literature, including neuropathological, clinical, neuroimaging, and neurophysiological features of the disease, and highlighting the controversies still unsolved in the differential diagnoses and the current diagnostic criteria. We also discussed the current knowledge gaps still present in both diagnostic and therapeutic fields when approaching this rare condition.
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OBJECTIVE: Motor Unit Number Estimation (MUNE) techniques are crucial in assessing lower motor neuron loss. MScanFit MUNE (MScanFit) is a novel tool which estimates MUNE values from compound muscle action potential (CMAP) scans by considering the probabilistic nature of motor unit firing. We conducted a prospective study to evaluate the diagnostic utility of MScanFit compared to quantitative electromyography (qEMG) in ALS patients. METHODS: We enrolled 35 patients diagnosed with amyotrophic lateral sclerosis (ALS) and 14 healthy controls, assessing qEMG and MScanFit MUNE in abductor pollicis brevis, abductor digiti minimi and tibialis anterior muscles. RESULTS: We found higher sensitivity of qEMG in detecting abnormalities compared to MScanFit, with a high concordance rate between the two techniques. Notably, a few muscles exhibited abnormal MUNE but normal qEMG findings, suggesting a potential complementary role for MScanFit in ALS diagnosis. Neurophysiological parameters from MScanFit showed good correlations with qEMG measures. Subclinical neurophysiological involvement was observed in muscles with normal strength, emphasizing the importance of sensitive diagnostic tools. CONCLUSION: MScanFit demonstrated validity in distinguishing ALS patients from healthy subjects and correlated well with qEMG parameters. SIGNIFICANCE: Our study confirmed the diagnostic utility of MScanFit MUNE in ALS, highlighting its role as a supplementary diagnostic tool.
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Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with a complex genetic architecture, showing monogenic, oligogenic, and polygenic inheritance. In this study, we describe the case of a 71 years-old man diagnosed with ALS with atypical clinical features consisting in progressive ocular ptosis and sensorineural deafness. Genetic analyses revealed two heterozygous variants, in the SOD1 (OMIM*147450) and the TBK1 (OMIM*604834) genes respectively, and furthermore mitochondrial DNA (mtDNA) sequencing identified the homoplasmic m.14484T>C variant usually associated with Leber's Hereditary Optic Neuropathy (LHON). We discuss how all these variants may synergically impinge on mitochondrial function, possibly contributing to the pathogenic mechanisms which might ultimately lead to the neurodegenerative process, shaping the clinical ALS phenotype enriched by adjunctive clinical features.
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Non-dystrophic myotonias include several entities with possible clinical overlap, i.e. myotonia congenita caused by CLCN1 gene mutations, as well as paramyotonia congenita and sodium channel myotonia caused by SCN4A gene mutations. Herein, we describe the clinical features of five relatives affected by clinical and neurophysiological myotonia, with an aspecific and mixed phenotype. Next-generation sequencing identified the novel p.K1302R variant in SCN4A and the p.H838P variant in CLCN1. Segregation of the two mutations with the disease was confirmed by genotyping affected and non-affected family members. Patch-clamp experiments showed that sodium currents generated by p.K1302R and WT hNav1.4 were very similar. Mutant channel showed a small negative shift (5 mV) in the voltage-dependence of activation, which increased the likelihood of the channel to open at more negative voltages. The p.H838P mutation caused a reduction in chloride current density and a small voltage-dependence shift towards less negative potentials, in agreement with its position into the CBS2 domain of the C-terminus. Our results demonstrated that the mild functional alterations induced by p.K1302R and p.H838P in combination may be responsible for the mixed myotonic phenotypes. The K1302R mutant was sensitive to mexiletine and lamotrigine, suggesting that both drugs might be useful for the K1302R carriers.
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Miotonía Congénita , Miotonía , Humanos , Canal de Sodio Activado por Voltaje NAV1.4 , Mutación , Miotonía/genética , Fenotipo , Canales de Cloruro/genéticaRESUMEN
Background: Oral tauroursodeoxycholic acid (TUDCA) is a commercial drug currently tested in patients with amyotrophic lateral sclerosis (ALS) both singly and combined with sodium phenylbutyrate. This retrospective study aimed to investigate, in a real-world setting, whether TUDCA had an impact on the overall survival of patients with ALS who were treated with this drug compared to those patients who received standard care only. Methods: This propensity score-matched study was conducted in the Emilia Romagna Region (Italy), which has had an ALS regional registry since 2009. Out of 627 patients with ALS diagnosed from January 1st, 2015 to June 30th, 2021 and recorded in the registry with available information on death/tracheostomy, 86 patients took TUDCA and were matched in a 1:2 ratio with patients who received only usual care according to age at onset, sex, phenotype, diagnostic latency, ALS Functional Rating Scale-Revised (ALSFRS-R) at first visit, disease progression rate at first visit, and BMI at diagnosis. The primary outcome was survival difference (time from onset of symptoms to tracheostomy/death) between TUDCA exposed and unexposed patients. Findings: A total of 86 patients treated with TUDCA were matched to 172 patients who did not receive treatment. TUDCA-exposed patients were stratified based on dosage (less than or equal to 1000 mg/day or greater) and duration (less than or equal to 12 months or longer) of treatment. The median overall survival was 49.6 months (95% CI 41.7-93.5) among those treated with TUDCA and 36.2 months (95% CI 32.7-41.6) in the control group, with a reduced risk of death observed in patients exposed to a higher dosage (defined as ≥ 1000 mg/day) of TUDCA (HR 0.56; 95% CI 0.38-0.83; p = 0.0042) compared to both the control group and those with lower TUDCA dosages (defined as < 1000 mg/day). TUDCA was generally well-tolerated, except for a minority of patients (n = 7, 8.1%) who discontinued treatment due to side effects, primarily gastrointestinal and mild in severity; only 2 adverse events required hospital access but resolved without sequelae. Interpretation: In this population-based exploratory study, patients with ALS who were treated with TUDCA may have prolonged survival compared to patients receiving standard care only. Additional prospective randomized studies are needed to confirm the efficacy and safety of this drug. Funding: Emilia-Romagna Region.
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Objective: Spinal Muscular Atrophy (SMA) is a genetic neuromuscular disease affecting the lower motor neuron, carrying a significant burden on patients' general motor skills and quality of life, characterized by a great variability in phenotypic expression. As new therapeutic options make their appearance on the scene, sensitive clinical tools and outcome measures are needed, especially in adult patients undergoing treatment, in which the expected clinical response is a mild improvement or stabilization of disease progression. Methods: Here, we describe a new functional motor scale specifically designed for evaluating the endurance dimension for the upper and lower limbs in adult SMA patients. Results: The scale was first tested in eight control healthy subjects and then validated in ten adult SMA patients, proving intra- and inter-observer reliability. We also set up an evaluation protocol by using wearable devices including surface EMG and accelerometer. Conclusions: The endurance evaluation should integrate the standard clinical monitoring in the management and follow-up of SMA adult patients.