RESUMEN
BACKGROUND: Dysphagia is a common symptom during the trajectory of ALS, and it can significantly impact on the quality of life and prognosis of patients. Nowadays, no specific tool for the screening of dysphagia in ALS is validated, and the approach is heterogeneous across the Italian centres. OBJECTIVE: To validate the DYALS (dysphagia in amyotrophic lateral sclerosis) questionnaire, adapting the DYMUS (dysphagia in multiple sclerosis) questionnaire, for the assessment of dysphagia in ALS patients, in order to uniform the evaluations across the Italian ALS network. METHODS: We included 197 patients diagnosed with ALS following the El Escorial criteria, in sixteen Italian ALS centres between 1st December 2019 and 1st July 2020. For each patient, we collected clinical and demographic data and obtained ALSFRS-r score, ALSAQ-5 score, DYMUS score, and EAT-10 score. RESULTS: Across the 197 patients, the ratio M/F was 113/84, and the median age was 64 years (IQR 56-72.5). Bulbar patients were 20%, and spinal patients 80%. The median ALSFRSr total score of patients was 35 (IQR 28-39). DYALS score was statistically higher in bulbar ALS than in spinal ALS (median = 6, IQR 4.5-9 vs median = 1, IQR 0-5, z = 6.253, p < 0.0001). DYALS questionnaire showed a high internal consistency (Cronbach's alpha = 0.88). There was a statistically significant correlation between DYALS and EAT-10 (rho = 0.90, p < 0.0001). CONCLUSIONS: DYALS scale is reliable, manageable, and easily usable for the screening of dysphagia in ALS. It can be shared with all the Italian ALS centres in order to collect uniform data for therapeutic strategies and clinical trials.
Asunto(s)
Esclerosis Amiotrófica Lateral , Trastornos de Deglución , Esclerosis Múltiple , Esclerosis Amiotrófica Lateral/complicaciones , Esclerosis Amiotrófica Lateral/diagnóstico , Trastornos de Deglución/diagnóstico , Trastornos de Deglución/etiología , Humanos , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico , Calidad de Vida , Encuestas y CuestionariosRESUMEN
BACKGROUND: Amyotrophic Lateral Sclerosis (ALS) is a degenerative disorder which affects the motor neurons. Growing evidence suggests that ALS may impact the metabolic system, including the glucose metabolism. Several studies investigated the role of Diabetes Mellitus (DM) as risk and/or prognostic factor. However, a clear correlation between DM and ALS has not been defined. In this review, we focus on the role of DM in ALS, examining the different hypotheses on how perturbations of glucose metabolism may interact with the pathophysiology and the course of ALS. METHODS: We undertook an independent PubMed literature search, using the following search terms: ((ALS) OR (Amyotrophic Lateral Sclerosis) OR (Motor Neuron Disease)) AND ((Diabetes) OR (Glucose Intolerance) OR (Hyperglycemia)). Review and original articles were considered. RESULTS: DM appears not to affect ALS severity, progression, and survival. Contrasting data suggested a protective role of DM on the occurrence of ALS in elderly and an opposite effect in younger subjects. CONCLUSIONS: The actual clinical and pathophysiological correlation between DM and ALS is unclear. Large longitudinal prospective studies are needed. Achieving large sample sizes comparable to those of common complex diseases like DM is a challenge for a rare disease like ALS. Collaborative efforts could overcome this specific issue.
Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Diabetes Mellitus/metabolismo , Glucosa/metabolismo , Factores de Edad , Esclerosis Amiotrófica Lateral/mortalidad , Esclerosis Amiotrófica Lateral/patología , Diabetes Mellitus/mortalidad , Diabetes Mellitus/patología , HumanosRESUMEN
Strong evidence suggests that endoplasmic reticulum stress plays a critical role in the pathogenesis of amyotrophic lateral sclerosis (ALS) through altered regulation of proteostasis. Robust preclinical findings demonstrated that guanabenz selectively inhibits endoplasmic reticulum stress-induced eIF2α-phosphatase, allowing misfolded protein clearance, reduces neuronal death and prolongs survival in in vitro and in vivo models. However, its safety and efficacy in patients with ALS are unknown. To address these issues, we conducted a multicentre, randomized, double-blind trial with a futility design. Patients with ALS who had displayed an onset of symptoms within the previous 18 months were randomly assigned in a 1:1:1:1 ratio to receive 64 mg, 32 mg or 16 mg of guanabenz or placebo daily for 6 months as an add-on therapy to riluzole. The purpose of the placebo group blinding was to determine safety but not efficacy. The primary outcome was the proportion of patients progressing to higher stages of disease within 6 months as measured using the ALS Milano-Torino staging system, compared with a historical cohort of 200 patients with ALS. The secondary outcomes were the rate of decline in the total revised ALS functional rating scale score, slow vital capacity change, time to death, tracheotomy or permanent ventilation and serum light neurofilament level at 6 months. The primary assessment of efficacy was performed using intention-to-treat analysis. The treatment arms using 64 mg and 32 mg guanabenz, both alone and combined, reached the primary hypothesis of non-futility, with the proportions of patients who progressed to higher stages of disease at 6 months being significantly lower than that expected under the hypothesis of non-futility and a significantly lower difference in the median rate of change in the total revised ALS functional rating scale score. This effect was driven by patients with bulbar onset, none of whom (0/18) progressed to a higher stage of disease at 6 months compared with those on 16 mg guanabenz (4/8; 50%), the historical cohort alone (21/49; 43%; P = 0.001) or plus placebo (25/60; 42%; P = 0.001). The proportion of patients who experienced at least one adverse event was higher in any guanabenz arm than in the placebo arm, with higher dosing arms having a significantly higher proportion of drug-related side effects and the 64 mg arm a significantly higher drop-out rate. The number of serious adverse events did not significantly differ between the guanabenz arms and the placebo. Our findings indicate that a larger trial with a molecule targeting the unfolded protein response pathway without the alpha-2 adrenergic related side-effect profile of guanabenz is warranted.
Asunto(s)
Agonistas de Receptores Adrenérgicos alfa 2/uso terapéutico , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Esclerosis Amiotrófica Lateral/metabolismo , Guanabenzo/uso terapéutico , Respuesta de Proteína Desplegada/fisiología , Agonistas de Receptores Adrenérgicos alfa 2/farmacología , Anciano , Esclerosis Amiotrófica Lateral/diagnóstico , Método Doble Ciego , Femenino , Guanabenzo/farmacología , Humanos , Masculino , Persona de Mediana Edad , Respuesta de Proteína Desplegada/efectos de los fármacosAsunto(s)
Encefalopatías/etiología , Infecciones por Enterobacteriaceae/complicaciones , Hiperamonemia/etiología , Vejiga Urinaria Neurogénica/complicaciones , Infecciones Urinarias/complicaciones , Accidentes por Caídas , Antibacterianos/uso terapéutico , Encefalopatías/diagnóstico , Encefalopatías/fisiopatología , Ciprofloxacina/uso terapéutico , Deshidratación/diagnóstico , Deshidratación/etiología , Electroencefalografía , Infecciones por Enterobacteriaceae/diagnóstico , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Femenino , Humanos , Hiperamonemia/diagnóstico , Hiperamonemia/fisiopatología , Hipernatremia/diagnóstico , Hipernatremia/etiología , Persona de Mediana Edad , Paraparesia/complicaciones , Providencia , Esquizofrenia/complicaciones , Intento de Suicidio , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/tratamiento farmacológicoRESUMEN
To identify novel genes associated with ALS, we undertook two lines of investigation. We carried out a genome-wide association study comparing 20,806 ALS cases and 59,804 controls. Independently, we performed a rare variant burden analysis comparing 1,138 index familial ALS cases and 19,494 controls. Through both approaches, we identified kinesin family member 5A (KIF5A) as a novel gene associated with ALS. Interestingly, mutations predominantly in the N-terminal motor domain of KIF5A are causative for two neurodegenerative diseases: hereditary spastic paraplegia (SPG10) and Charcot-Marie-Tooth type 2 (CMT2). In contrast, ALS-associated mutations are primarily located at the C-terminal cargo-binding tail domain and patients harboring loss-of-function mutations displayed an extended survival relative to typical ALS cases. Taken together, these results broaden the phenotype spectrum resulting from mutations in KIF5A and strengthen the role of cytoskeletal defects in the pathogenesis of ALS.
Asunto(s)
Esclerosis Amiotrófica Lateral/diagnóstico , Esclerosis Amiotrófica Lateral/genética , Estudio de Asociación del Genoma Completo/métodos , Cinesinas/genética , Mutación con Pérdida de Función/genética , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Aminoácidos , Esclerosis Amiotrófica Lateral/epidemiología , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
INTRODUCTION: Recent studies suggest that endoplasmic reticulum stress may play a critical role in the pathogenesis of amyotrophic lateral sclerosis (ALS) through an altered regulation of the proteostasis, the cellular pathway-balancing protein synthesis and degradation. A key mechanism is thought to be the dephosphorylation of eIF2α, a factor involved in the initiation of protein translation. Guanabenz is an alpha-2-adrenergic receptor agonist safely used in past to treat mild hypertension and is now an orphan drug. A pharmacological action recently discovered is its ability to modulate the synthesis of proteins by the activation of translational factors preventing misfolded protein accumulation and endoplasmic reticulum overload. Guanabenz proved to rescue motoneurons from misfolding protein stress both in in vitro and in vivo ALS models, making it a potential disease-modifying drug in patients. It is conceivable investigating whether its neuroprotective effects based on the inhibition of eIF2α dephosphorylation can change the progression of ALS. METHODS AND ANALYSES: Protocolised Management In Sepsis is a multicentre, randomised, double-blind, placebo-controlled phase II clinical trial with futility design. We will investigate clinical outcomes, safety, tolerability and biomarkers of neurodegeneration in patients with ALS treated with guanabenz or riluzole alone for 6 months. The primary aim is to test if guanabenz can reduce the proportion of patients progressed to a higher stage of disease at 6 months compared with their baseline stage as measured by the ALS Milano-Torino Staging (ALS-MITOS) system and to the placebo group. Secondary aims are safety, tolerability and change in at least one biomarker of neurodegeneration in the guanabenz arm compared with the placebo group. Findings will provide reliable data on the likelihood that guanabenz can slow the course of ALS in a phase III trial. ETHICS AND DISSEMINATION: The study protocol was approved by the Ethics Committee of IRCCS 'Carlo Besta Foundation' of Milan (Eudract no. 2014-005367-32 Pre-results) based on the Helsinki declaration.
Asunto(s)
Agonistas de Receptores Adrenérgicos alfa 2/farmacología , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Estrés del Retículo Endoplásmico/efectos de los fármacos , Guanabenzo/farmacología , Deficiencias en la Proteostasis/tratamiento farmacológico , Edad de Inicio , Esclerosis Amiotrófica Lateral/fisiopatología , Progresión de la Enfermedad , Método Doble Ciego , Humanos , Italia , Inutilidad Médica , Fármacos Neuroprotectores , Deficiencias en la Proteostasis/fisiopatologíaRESUMEN
A patient has been recently described with frontotemporal cognitive decline and C9orf72 repeat expansion who presented abnormally slowed background and photoparoxysmal response at electroencephalographic (EEG) recording. Our data, based on five patients with repeat expansions in C9orf72 and EEG recordings suggest that abnormally slowed background and epilepsy represent previously unrecognized features of the C9orf72 phenotype in some patients.
Asunto(s)
Expansión de las Repeticiones de ADN/genética , Epilepsia/genética , Epilepsia/fisiopatología , Proteínas/genética , Proteína C9orf72 , Diabetes Mellitus Tipo 2/complicaciones , Electroencefalografía , Electromiografía , Femenino , Humanos , Hipertensión/complicaciones , Persona de Mediana EdadRESUMEN
Olanzapine-related seizures have rarely been reported despite associated proconvulsant risk factors described in the literature: myoclonic status, increased frequency of seizures, tonic-clonic seizures, as well as fatal status epilepticus. We present a psychiatric patient who developed repetitive focal motor seizures and lingual dystonia when olanzapine was added for psychomotor agitation and aggressiveness. Olanzapine was immediately suspended and the seizures progressively disappeared. A control EEG showed no paroxysmal discharges. Olanzapine shares some pharmacological similarities with clozapine, a neuroleptic with a high risk of dose-dependent seizures. This adverse effect should be taken into account, and olanzapine should be used with caution if concomitant circumstances decrease the seizure threshold. [Published with video sequence online].
Asunto(s)
Antipsicóticos/efectos adversos , Benzodiazepinas/efectos adversos , Distonía/inducido químicamente , Epilepsia Parcial Motora/inducido químicamente , Convulsiones/inducido químicamente , Distonía/tratamiento farmacológico , Electroencefalografía/métodos , Epilepsia Parcial Motora/diagnóstico , Epilepsia Parcial Motora/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Olanzapina , Convulsiones/complicaciones , Convulsiones/tratamiento farmacológicoRESUMEN
There are indications that both familial amyotrophic lateral sclerosis (ALS) and sporadic ALS phenotype and prognosis are partly regulated by genetic and environmental factors, supporting the theory that ALS is a multifactorial disease. The aim of this article was to assess the role of ATXN2 intermediate length repeats in a large series of Italian and Sardinian ALS patients and controls carrying a pathogenetic C9ORF72 GGGGCC hexanucleotide repeat. A total of 1972 ALS cases were identified through the database of the Italian ALS Genetic consortium, a collaborative effort including 18 ALS centers throughout Italy. The study population included: (1) 276 Italian and 57 Sardinian ALS cases who carried the C9ORF72 expansion; (2) 1340 Italian and 299 Sardinian ALS cases not carrying the C9ORF72 expansion. A total of healthy 1043 controls were also assessed. Most Italian and Sardinian cases and controls were homozygous for 22/22 or 23/23 repeats or heterozygous for 22/23 repeats of the ATXN2 gene. ATXN2 intermediate length repeats alleles (≥28) were detected in 3 (0.6%) Italian ALS cases carrying the C9ORF72 expansion, in none of the Sardinian ALS cases carrying the expansion, in 60 (4.3%) Italian cases not carrying the expansion, and in 6 (2.0%) Sardinian ALS cases without C9ORF72 expansion. Intermediate length repeat alleles were found in 12 (1.5%) Italian controls and 1 (0.84%) Sardinian controls. Therefore, ALS patients with C9ORF72 expansion showed a lower frequency of ATXN2 polyQ intermediate length repeats than both controls (Italian cases, p = 0.137; Sardinian cases, p = 0.0001) and ALS patients without C9ORF72 expansion (Italian cases, p = 0.005; Sardinian cases, p = 0.178). In our large study on Italian and Sardinian ALS patients with C9ORF72 GGGGCC hexanucleotide repeat expansion, compared to age-, gender- and ethnic-matched controls, ATXN2 polyQ intermediate length does not represent a modifier of ALS risk, differently from non-C9ORF72 mutated patients.
Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Ataxina-2/genética , Expansión de las Repeticiones de ADN/genética , Estudios de Asociación Genética , Proteínas/genética , Anciano , Proteína C9orf72 , Femenino , Humanos , Italia , Masculino , Persona de Mediana EdadRESUMEN
Akinetic crisis (AC) is a life-threatening complication of parkinsonism characterized by an acute severe akinetic-hypertonic state, consciousness disturbance, hyperthermia, and muscle enzymes elevation. Injectable dopaminomimetic drugs, high-dose methylprednisolone, and dantrolene are advocated as putative specific treatments. The course of the illness is frequently complicated by infections, pulmonary embolism, renal failure, disseminated intravascular coagulation, and cardiac arrhythmias. Critical illness neuromyopathy (CINM) is an acquired neuromuscular disorder characterized by flaccid quadriparesis and muscle enzyme elevation, often occurring in intensive care units and primarily associated with inactivity, sepsis, multiorgan failure, neuromuscular blocking agents, and steroid treatment. In 3 parkinsonian patients, during the course of AC we observed disappearance of rigidity but persistent hypoactivity. In all, neurological examination showed quadriparesis with loss of tendon reflexes and laboratory investigation disclosed a second peak of muscle enzymes elevation, following the first increment due to AC. Electrophysiological studies showed absent or reduced sensory nerve action potentials and compound muscular action potentials, myopathic changes, and fibrillation potentials at electromyography recordings, and reduced excitability or inexcitability of tibialis anterior at direct muscle stimulation, leading to a diagnosis of CINM in all 3 patients. In 1 patient, the diagnosis was also confirmed by muscle biopsy. Outcome was fatal in 2 of the 3 patients. Although AC is associated with most of the known risk factors for CINM, the cooccurrence of the 2 disorders may be difficult to recognize and has never been reported. We found that CINM can occur as a severe complication of AC, and should be suspected when hypertonia-rigidity subsides despite persistent akinesia. Strict monitoring of muscle enzyme levels may help diagnosis. This finding addresses possible caveats in the use of putative treatments for AC.
Asunto(s)
Enfermedades Neuromusculares/etiología , Enfermedad de Parkinson/complicaciones , Anciano , Anciano de 80 o más Años , Femenino , Humanos , MasculinoRESUMEN
OBJECTIVE: To assess the efficacy of recombinant human erythropoietin (rhEPO) in amyotrophic lateral sclerosis (ALS). METHODS: Patients with probable laboratory-supported, probable or definite ALS were enrolled by 25 Italian centres and randomly assigned (1:1) to receive intravenous rhEPO 40,000â IU or placebo fortnightly as add-on treatment to riluzole 100â mg daily for 12â months. The primary composite outcome was survival, tracheotomy or >23â h non-invasive ventilation (NIV). Secondary outcomes were ALSFRS-R, slow vital capacity (sVC) and quality of life (ALSAQ-40) decline. Tolerability was evaluated analysing adverse events (AEs) causing withdrawal. The randomisation sequence was computer-generated by blocks, stratified by centre, disease severity (ALSFRS-R cut-off score of 33) and onset (spinal or bulbar). The main outcome analysis was performed in all randomised patients and by intention-to-treat for the entire population and patients stratified by severity and onset. The study is registered, EudraCT 2009-016066-91. RESULTS: We randomly assigned 208 patients, of whom 5 (1 rhEPO and 4 placebo) withdrew consent and 3 (placebo) became ineligible (retinal thrombosis, respiratory insufficiency, SOD1 mutation) before receiving treatment; 103 receiving rhEPO and 97 placebo were eligible for analysis. At 12â months, the annualised rate of death (rhEPO 0.11, 95% CI 0.06 to 0.20; placebo: 0.08, CI 0.04 to 0.17), tracheotomy or >23â h NIV (rhEPO 0.16, CI 0.10 to 0.27; placebo 0.18, CI 0.11 to 0.30) did not differ between groups, also after stratification by onset and ALSFRS-R at baseline. Withdrawal due to AE was 16.5% in rhEPO and 8.3% in placebo. No differences were found for secondary outcomes. CONCLUSIONS: RhEPO 40,000â IU fortnightly did not change the course of ALS.
Asunto(s)
Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Eritropoyetina/uso terapéutico , Adulto , Anciano , Esclerosis Amiotrófica Lateral/mortalidad , Método Doble Ciego , Epoetina alfa , Eritropoyetina/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéutico , Resultado del TratamientoRESUMEN
Natura non facit saltus (Latin for "nature does not make jumps") is a maxim expressing the idea that natural things and properties change gradually, in a continuum, rather than suddenly. In biomedical sciences, for taxonomic purposes, we make jumps that emphasize differences more than similarities. Among the dysimmune neuropathies, 2 disorders, characterized by the presence of antibodies to gangliosides GM1 and GD1a and a peculiar, exclusive motor involvement, have been identified: acute motor axonal neuropathy (AMAN) and multifocal motor neuropathy (MMN). However, anti-GM1 or -GD1a antibodies are also associated with acute motor and sensory axonal motor neuropathy (AMSAN). We review the results of recent clinical and experimental studies showing that AMAN and MMN are not exclusively motor. We discuss the possible explanations for the greater resistance of sensory fibers to antibody attack to finally suggest that AMAN, AMSAN, and MMN belong to a continuous spectrum with a common pathophysiological mechanism.
Asunto(s)
Autoanticuerpos/efectos adversos , Gangliósidos/inmunología , Polineuropatías/inmunología , Reacciones Antígeno-Anticuerpo/inmunología , Humanos , Oligosacáridos/inmunología , Polineuropatías/clasificaciónRESUMEN
BACKGROUND: Acute motor axonal neuropathy (AMAN) and acute motor and sensory axonal neuropathy (AMSAN) are due to an antiganglioside antibody mediated attack, thought to be restricted to motor fibres in AMAN. Sensory symptoms and minor sensory conduction abnormalities, however, have been reported in some AMAN patients. OBJECTIVE: To verify whether sensory fibres are truly spared in AMAN and whether AMAN and AMSAN represent a continuum. METHODS: Serial conduction studies in 13 AMAN and three AMSAN patients were reviewed. To evaluate the variation in sensory nerve action potential (SNAP) amplitude in serial recordings, the least significant change in a test-retest study of 20 controls was calculated. Least significant change for median, ulnar and sural nerves were 44%, 47% and 58%, respectively. RESULTS: In 34% of initially normal sensory nerves of six AMAN patients, SNAP amplitude significantly increased by 57-518%. In three nerves of three AMAN patients, SNAP significantly decreased by 50-69%. Overall, serial recordings allowed detection of sensory fibre involvement in 49% of nerves and in 69% of AMAN patients. In one AMSAN patient, SNAP increased in two nerves by 150-300%; in another patient, SNAPs, unrecordable at baseline in six nerves, reappeared during follow-up and normalised in three nerves. In five nerves of three AMAN and in eight nerves of two AMSAN patients, SNAP amplitudes increased rapidly, suggesting reversible conduction failure of sensory fibres. In other nerves, SNAP increased over months, as for axonal regeneration. CONCLUSIONS: Sensory fibres are often involved subclinically in AMAN. Reversible conduction failure may develop in sensory as well as motor fibres in both AMAN and AMSAN. AMAN and AMSAN represent a continuum in axonal GBS.
Asunto(s)
Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/fisiopatología , Células Receptoras Sensoriales/fisiología , Potenciales de Acción/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Conducción Nerviosa/fisiologíaRESUMEN
We report 2 patients diagnosed simultaneously with an overlap of Guillain-Barré syndrome (GBS) and Miller Fisher syndrome (MFS), who had anti-GT1a, anti-GQ1b, anti-GD1a and anti-GD1b antibodies. There was no identifiable specific preceding infection. Both patients presented with upper and lower limb paresthesias and severe weakness, bulbar and facial weakness, ophthalmoparesis and areflexia. In one, electrophysiology demonstrated multifocal conduction blocks (CBs) and mild motor conduction velocity slowing in intermediate segments and absent sensory nerve action potentials (SNAPs). The patient improved rapidly and fully recovered within 18 days from onset. CBs resolved, distal compound muscle action potential (CMAP) amplitudes increased and SNAPs normalized on subsequent testing. In the other patient, initial studies showed low/normal CMAPs, with absent SNAPs, without demyelinating features. This patient fully recovered within 21 days from onset. CMAPs markedly increased, SNAPs improved marginally. These 2 patients exhibited features indicative of the pathophysiological mechanism of conduction failure in motor and sensory fibers. This phenomenon relates to rapidly resolving CBs possibly induced by the transitory and limited attack of antiganglioside antibodies at the axolemma of the nodes of Ranvier not progressing to axonal degeneration. These cases widen the range of GBS subtypes in which reversible conduction failure has been described, to include overlap syndromes with MFS. The factors determining the electrophysiology, as well as the rate, degree and quality of recovery in GBS subtypes remain uncertain at the present time.
Asunto(s)
Síndrome de Guillain-Barré/fisiopatología , Síndrome de Miller Fisher/fisiopatología , Neuronas Motoras/fisiología , Conducción Nerviosa/fisiología , Células Receptoras Sensoriales/fisiología , Potenciales de Acción/fisiología , Adulto , Autoanticuerpos/inmunología , Axones/patología , Estimulación Eléctrica , Fenómenos Electrofisiológicos , Femenino , Gangliósidos/inmunología , Síndrome de Guillain-Barré/complicaciones , Humanos , Síndrome de Miller Fisher/complicaciones , Debilidad Muscular/etiología , Examen Neurológico , Parestesia/etiología , Infecciones del Sistema Respiratorio/complicaciones , Trastornos del Habla/etiologíaRESUMEN
OBJECTIVE: To electrophysiologically classify an Italian Guillain-Barré syndrome (GBS) population into demyelinating and axonal subtypes, to investigate how serial recordings changed the classification and to underline the pitfalls in electrodiagnosis of GBS subtypes. METHODS: The authors applied two current electrodiagnostic criteria sets for demyelinating and axonal GBS subtypes in 55 patients who had at least two serial recordings in three motor and sensory nerves. RESULTS: At first test, the electrodiagnosis was almost identical with both criteria: 65-67% of patients were classifiable as acute inflammatory demyelinating polyradiculoneuropathy (AIDP), 18% were classifiable as axonal GBS, and 14-16% were equivocal. At follow-up, 24% of patients changed classification: AIDP decreased to 58%, axonal GBS increased to 38%, and equivocal patients decreased to 4%. The majority of shifts were from AIDP and equivocal groups to axonal GBS, and the main reason was the recognition by serial recordings of the reversible conduction failure and of the length-dependent compound muscle action potential amplitude reduction patterns as expression of axonal pathology. CONCLUSIONS: Axonal GBS is pathophysiologically characterised not only by axonal degeneration but also by reversible conduction failure at the axolemma of the Ranvier node. The lack of distinction among demyelinating conduction block, reversible conduction failure and length-dependent compound muscle action potential amplitude reduction may fallaciously classify patients with axonal GBS as having AIDP. Serial electrophysiological studies are mandatory for proper diagnosis of GBS subtypes and the identification of pathophysiological mechanisms of muscle weakness. More reliable electrodiagnostic criteria taking into consideration the reversible conduction failure pattern should be devised.
Asunto(s)
Electrodiagnóstico/métodos , Síndrome de Guillain-Barré/clasificación , Síndrome de Guillain-Barré/diagnóstico , Infecciones por Campylobacter/complicaciones , Gangliósidos/inmunología , Síndrome de Guillain-Barré/complicaciones , Síndrome de Guillain-Barré/fisiopatología , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Conducción Nerviosa/fisiologíaRESUMEN
In two patients with the pharyngeal-cervical-brachial variant (PCB) of Guillain-Barré syndrome (GBS), low amplitude distal compound muscle action potentials and partial motor conduction blocks normalized without development of excessive temporal dispersion within 4 weeks. Sensory nerve action potentials significantly improved in amplitude or, when absent, rapidly became recordable at follow-up. Besides axonal degeneration, PCB is characterized by reversible conduction failure in both motor and sensory fibers and is in the continuous spectrum of axonal GBS subtypes.
Asunto(s)
Brazo , Síndrome de Guillain-Barré/fisiopatología , Debilidad Muscular , Músculo Esquelético/fisiopatología , Músculos del Cuello/fisiopatología , Conducción Nerviosa , Hombro , Potenciales de Acción , Anciano , Axones , Estudios de Seguimiento , Síndrome de Guillain-Barré/clasificación , Humanos , Masculino , Persona de Mediana Edad , Neuronas Motoras , Degeneración Nerviosa , Células Receptoras SensorialesAsunto(s)
Síndrome de Guillain-Barré/clasificación , Síndrome de Guillain-Barré/diagnóstico , Enfermedades del Sistema Nervioso Periférico/clasificación , Enfermedades del Sistema Nervioso Periférico/diagnóstico , Infecciones por Campylobacter/diagnóstico , Campylobacter jejuni , Enteritis/diagnóstico , Enteritis/microbiología , Gangliósidos/inmunología , Síndrome de Guillain-Barré/inmunología , Humanos , Inmunoglobulina G/sangre , Enfermedades del Sistema Nervioso Periférico/inmunologíaRESUMEN
We evaluated serum glial fibrillary acidic protein (GFAP) levels by enzyme-linked immunosorbent assay (ELISA) in controls (n = 30) and in patients with chronic sensory-motor axonal neuropathy (CSMAN) (n = 30), chronic inflammatory demyelinating polyneuropathy (CIDP) (n = 30), multifocal motor neuropathy (MMN) (n = 30), and primary muscular spinal atrophy (PMSA) (n = 15). GFAP levels, expressed as optical density, were increased in CSMAN (median = 1.05) compared to controls (median = 0.41; P < 0.05) and CIDP (median = 0.53, P < 0.05). They were also increased in PMSA (median = 0.99) compared to controls (P < 0.05) and MMN (median = 0.66; P < 0.05). To differentiate CSMAN from CIDP and PMSA from MMN, we applied a cutoff of GFAP levels at 0.66, and we obtained good sensitivity and specificity. In neuropathies, serum GFAP correlated with summated sensory nerve action potential amplitudes (r = -0.57; P = 0.0006) and disease severity (r = 0.37; P = 0.0011). Thus, we propose serum GFAP as a marker of axonal damage and severity in chronic neuropathies.
Asunto(s)
Axones/patología , Proteína Ácida Fibrilar de la Glía/sangre , Polirradiculoneuropatía/sangre , Polirradiculoneuropatía/patología , Adolescente , Adulto , Enfermedad Crónica , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Neuropatía Hereditaria Motora y Sensorial/sangre , Neuropatía Hereditaria Motora y Sensorial/patología , Neuropatía Hereditaria Motora y Sensorial/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Polirradiculoneuropatía/clasificación , Polirradiculoneuropatía/fisiopatología , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/sangre , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/patología , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/fisiopatología , Curva ROC , Nervio Sural/patología , Nervio Sural/fisiopatología , Adulto JovenRESUMEN
Extreme carpal tunnel syndrome (CTS) is characterized by severe thenar atrophy, plegia of the abductor pollicis brevis (APB), fixed sensory deficit in the median nerve distribution, and absence of median motor and sensory responses on electrophysiological examination. In this study we report long-term follow-up of 37 patients with extreme CTS. Of the 24 patients with idiopathic extreme CTS, 9 were untreated, and 3 received conservative treatment. At follow-up, none of these patients showed objective or electrophysiological improvement, and all but 1 still reported positive symptoms. Conversely, 12 patients (14 hands) who underwent carpal tunnel release showed: resolution of positive symptoms in all but 1 hand; reappearance of median compound muscle action potentials (4.2 +/- 0.6 mV); reappearance of sensory nerve action potentials in all but 1 (7.9 +/- 0.8 microV); improvement of APB strength to grade 4 or 5 on the Medical Research Council scale in 11 hands; and resolution of hypesthesia in 1 hand. Six of 13 patients with non-idiopathic extreme CTS were operated. Of the 6, we found no or poor reinnervation in 3 patients, restoration of nerve responses and normal APB strength but no relief from pain and/or paresthesia in 2, and full recovery in 1. If untreated, extreme CTS is an irreversible condition. Although the outcome is considered to be disappointing in such cases, carpal tunnel release provides long-term relief, significant sensorimotor reinnervation, and improvement of motor deficit in most patients. It should be considered to be the first-choice treatment for idiopathic extreme CTS. Associated diseases do not necessarily imply a poor surgical outcome.