RESUMO
INTRODUCTION: Multifocal motor neuropathy (MMN) is a chronic progressive immune-mediated neuropathy, predominantly involving upper limbs asymmetrically with electrophysiologic evidence of motor conduction block. The treatment of choice is immunoglobulin (Ig). Nevertheless, some patients may become resistant to treatment. We describe a patient with history of MMN who became resistant to gammaglobulin treatment but markedly improved using ultra-high doses of intravenous immunoglobulin. CASE REPORT: A 36-year-old woman with diagnosis of MMN. After 5 years of clinical stability under subcutaneous Ig (2g/kg/month) the patient developed bilateral weakness involving both hands. Treatment was switched to intravenous Ig 2g/kg/month, nevertheless, she progressed and became totally dependent for activities of daily living. We started ultra-high dose intravenous immunoglobulin 5 g/kg/month, with good response. She became independent for activities of daily living and returned to work. The only treatment related adverse event was headache during infusion. CONCLUSION: Ultra-high dose intravenous Ig seems to be a useful therapy in aggressive MMN with severe disability despite conventional treatment. A low cardiovascular risk score (QRISK2 less than 10%) and a daily intravenous Ig lower than 35 g reduce the risk of severe complications related to intravenous Ig.
TITLE: Dosis ultraaltas de inmunoglobulina endovenosa mejoran la fuerza y la funcionalidad motora en una paciente con neuropatía motora multifocal refractaria.Introducción. La neuropatía motora multifocal (NMM) es una enfermedad crónica, progresiva e inmunomediada que afecta predominantemente a los miembros superiores de forma asimétrica. En los estudios electrofisiológicos se evidencian bloqueos en la conducción motora, y el tratamiento de elección es la inmunoglobulina humana (Ig); sin embargo, algunos pacientes pueden desarrollar refractariedad a este tratamiento. Describimos el caso de una paciente con diagnóstico de NMM que desarrolló refractariedad a la gammaglobulina y que mejoró marcadamente con dosis ultraaltas de esta misma medicación. Caso clínico. Mujer de 36 años, con diagnóstico de NMM, que, después de cinco años de estabilidad clínica bajo tratamiento con Ig subcutánea en dosis de 2 g/kg/mes, evolucionó con grave debilidad en ambas manos, por lo que se decidió cambiar el tratamiento a Ig endovenosa. No obstante, progresó hasta quedar incapacitada para realizar actividades básicas de la vida diaria. Iniciamos tratamiento con Ig endovenosa en dosis ultraaltas (5 g/kg/mes) con buena respuesta, logrando independencia funcional en las actividades de la vida diaria y que regresara al trabajo. El único evento adverso relacionado con la Ig endovenosa en dosis ultraaltas fue la presencia de cefalea durante la infusión. Conclusión. La Ig endovenosa en dosis ultraaltas parece ser un tratamiento efectivo para pacientes con NMM y grave discapacidad no respondedores a dosis convencionales. Un bajo índice de riesgo cardiovascular (QRISK2 menor que 10%) y una dosis diaria de Ig endovenosa menor de 35 g reducen el riesgo de complicaciones graves relacionadas con el uso de esta medicación.
Assuntos
Doença dos Neurônios Motores , Polineuropatias , Feminino , Humanos , Adulto , Imunoglobulinas Intravenosas/uso terapêutico , Atividades Cotidianas , Extremidade SuperiorRESUMO
INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic is a major worldwide health disorder. There is an increasing number of neurological complications recognized with COVID-19 including patients with GBS and its variants. DEVELOPMENT: A review of the clinical cases of GBS associated to COVID-19 infection published in the last months has been developed. We included 48 patients (31 men, mean age 56.4 years). The most common COVID-19 symptoms were cough (60.4%) and fever (56.3%). Mean time from COVID-19 symptoms to neurologic manifestations was 12.1 days, but in nine patients (18.8%) developed GBS within seven days. Eleven patients (22.9%) presented cranial nerve involvement in the absence of muscle weakness; 36 presented the classic sensory motor variant (75%) and one had a pure motor variant (2.1%). The electrodiagnostic pattern was considered demyelinating in 82.4% of the generalized variants. The presence of hyposmia/dysgeusia was associated with a latency shorter than seven days to GBS onset of symptoms (30% vs 15.6%), and cranial nerve involvement in the absence of weakness (30.8% vs 17.1%). Most patients (87.5%) were treated with intravenous immunoglobulin. Neurological outcome was favorable in 64.6%; 29.2% had respiratory failure and 4.2% died shortly after being admitted. CONCLUSIONS: GBS in patients with SARS-CoV-2 infection resembles clinically and electrophysiology the classical forms. Further studies are necessary to understand whether GBS frequency is actually increased due to SARS-CoV-2 infection and explore pathogenic mechanisms.
TITLE: Síndrome de Guillain-Barré asociado a infección por COVID-19: revisión de casos publicados.Introducción. La pandemia por la enfermedad por coronavirus 2019 (COVID-19) es un importante problema para la salud mundial. Hay un incremento en las complicaciones neurológicas reconocidas por la COVID-19, incluyendo el síndrome de Guillain-Barré (SGB) y sus variantes. Desarrollo. Se realizó una revisión de los casos publicados en los últimos meses de SGB asociado a infección por COVID-19. Incluimos a 48 pacientes (31 hombres; edad media: 56,4 años). Los síntomas de COVID-19 más comunes fueron tos (60,4%) y fiebre (56,3%). El tiempo promedio entre los síntomas de COVID-19 y el SGB fue de 12,1 días, pero nueve pacientes (18,8%) desarrollaron SGB en menos de siete días. Once pacientes (22,9%) presentaron afectación de los nervios craneales en ausencia de debilidad muscular, 36 presentaron la variante clásica sensitivomotora (75%) y uno tuvo una variante motora pura (2,1%). El patrón electrofisiológico se consideró desmielinizante en el 82,4% de las variantes generalizadas. La presencia de hiposmia/disgeusia estuvo asociada con una latencia menor a los siete días hasta el inicio de los síntomas del SGB (30 frente a 15,6%) y a la afectación de los nervios craneales en ausencia de debilidad (30,8 frente a 17,1%). La mayoría de los pacientes (87,5%) fueron tratados con inmunoglobulina endovenosa. La evolución neurológica fue favorable en el 64,6%, el 29,2% tuvo insuficiencia respiratoria y hubo un 4,2% de muertes. Conclusiones. El SGB en pacientes con infección por SARS-CoV-2 es similar clínica y electrofisiológicamente a las formas clásicas. Se requieren más estudios para comprender si la frecuencia del SGB realmente aumentó debido a la pandemia por COVID-19 y explorar los mecanismos patógenos involucrados.
Assuntos
COVID-19/complicações , Síndrome de Guillain-Barré/etiologia , Pandemias , SARS-CoV-2 , Adolescente , Adulto , Idoso , Anosmia/etiologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Autoantígenos/imunologia , Doenças dos Nervos Cranianos/etiologia , Disgeusia/etiologia , Feminino , Gangliosídeos/imunologia , Síndrome de Guillain-Barré/líquido cefalorraquidiano , Síndrome de Guillain-Barré/imunologia , Síndrome de Guillain-Barré/terapia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Masculino , Pessoa de Meia-Idade , Plasmaferese , Insuficiência Respiratória/etiologia , Estudos Retrospectivos , Avaliação de Sintomas , Resultado do Tratamento , Adulto JovemRESUMO
TITLE: Signo del tridente en la neurosarcoidosis medular.
Assuntos
Doenças do Sistema Nervoso Central/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Sarcoidose/diagnóstico por imagem , Medula Espinal/diagnóstico por imagem , Corticosteroides/uso terapêutico , Adulto , Anti-Inflamatórios/uso terapêutico , Doenças do Sistema Nervoso Central/tratamento farmacológico , Doenças do Sistema Nervoso Central/patologia , Diagnóstico Diferencial , Células Gigantes/ultraestrutura , Granuloma/diagnóstico por imagem , Histiócitos/ultraestrutura , Humanos , Masculino , Neuromielite Óptica/diagnóstico , Sarcoidose/tratamento farmacológico , Sarcoidose/patologia , Medula Espinal/patologia , Neoplasias da Medula Espinal/diagnóstico , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Nonconvulsive status epilepticus (NCSE) is a usually underdiagnosed and potentially treatable cause of altered awareness in the elderly. To assess etiologies, associations with other medical problems, and prognosis of NCSE in a population aged >75 years we performed a nested case-control study. METHODS: We retrospectively evaluated the clinical manifestations and EEG findings in 19 consecutive elderly patients (mean age 83.3 years) presenting with NCSE and compared them with 34 elderly patients (mean age 83.3 years) with altered mental status but without EEG evidence of NCSE. The variables compared included brain lesions on CT or MRI, number of concomitant chronic active diseases, previous neurological disorders, acute medical problems, the use and withdrawal of medications, and outcome. Statistical analysis was performed using chi-square test, t-test, Fisher's exact two-tailed test, and Wilcoxon rank sum test. RESULTS: The etiology of NCSE was epilepsy in 2, acute medical disorders in 14, and a cryptogenic cause in 4. The NCSE group had a more frequent history of epilepsy, 35% versus 8.8% (p = 0.028); tramadol use, 31% versus 0% (p = 0.00151); longer hospitalization, 25 days versus 7 days (p = 0.0004); and unfavorable outcome, 50% versus 5.8% (p = 0.00031). No significant differences were found in the other variables. Unfavorable outcome was associated with a higher number of comorbidities (>2) and to a severely altered mental status. CONCLUSIONS: NCSE is a serious cause of altered mental status in the elderly. Although its direct role in brain damage is controversial, elderly patients with NCSE have higher morbidity and worst prognosis than those with altered mental status without NCSE.
Assuntos
Eletroencefalografia/estatística & dados numéricos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Encefalopatias/diagnóstico , Encefalopatias/epidemiologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Comorbidade , Grupos Controle , Epilepsia/diagnóstico , Epilepsia/epidemiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Avaliação de Resultados em Cuidados de Saúde , Prognóstico , Estudos Retrospectivos , Estatísticas não Paramétricas , Estado Epiléptico/diagnóstico , Estado Epiléptico/epidemiologia , Tomografia Computadorizada por Raios XRESUMO
An HIV-1-infected patient with progressive multifocal leukoencephalopathy presented clinical deterioration and contrast-enhancing lesions on brain nuclear MR after the initiation of highly active antiretroviral therapy (HAART). Brain biopsy identified an inflammatory reaction compatible with immune reconstitution inflammatory syndrome. Treatment with corticosteroids and transient suppression of HAART led to marked neurologic improvement.
Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Encéfalo/efeitos dos fármacos , Encefalite/induzido quimicamente , Encefalite/imunologia , Leucoencefalopatia Multifocal Progressiva/tratamento farmacológico , Adulto , Anti-Inflamatórios/uso terapêutico , Afasia/induzido quimicamente , Afasia/imunologia , Afasia/fisiopatologia , Encéfalo/imunologia , Encéfalo/patologia , Quimiotaxia de Leucócito/efeitos dos fármacos , Quimiotaxia de Leucócito/imunologia , Dexametasona/uso terapêutico , Encefalite/fisiopatologia , Hemiplegia/induzido quimicamente , Hemiplegia/imunologia , Hemiplegia/fisiopatologia , Humanos , Corpos de Inclusão/imunologia , Corpos de Inclusão/patologia , Corpos de Inclusão/virologia , Vírus JC/imunologia , Vírus JC/isolamento & purificação , Leucoencefalopatia Multifocal Progressiva/fisiopatologia , Leucoencefalopatia Multifocal Progressiva/virologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Imageamento por Ressonância Magnética , Masculino , Oligodendroglia/imunologia , Oligodendroglia/patologia , Oligodendroglia/virologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Resultado do Tratamento , Suspensão de TratamentoAssuntos
Cefaleia/etiologia , Cefaleia/fisiopatologia , Cervicalgia/etiologia , Cervicalgia/fisiopatologia , Dissecação da Artéria Vertebral/fisiopatologia , Artéria Vertebral/fisiopatologia , Adulto , Fatores Etários , Idoso , Angiografia Cerebral , Diagnóstico Diferencial , Progressão da Doença , Diagnóstico Precoce , Feminino , Cefaleia/patologia , Humanos , Ataque Isquêmico Transitório/etiologia , Ataque Isquêmico Transitório/patologia , Ataque Isquêmico Transitório/fisiopatologia , Síndrome Medular Lateral/etiologia , Síndrome Medular Lateral/patologia , Síndrome Medular Lateral/fisiopatologia , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Cervicalgia/patologia , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/patologia , Dissecação da Artéria Vertebral/diagnóstico por imagem , Dissecação da Artéria Vertebral/patologiaAssuntos
Transtornos de Enxaqueca/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneurisma/patologia , Angiografia , Artéria Carótida Interna/patologia , Criança , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/patologiaRESUMO
Reflex activation of seizures by thoughts or mental images is suggested by patients but has not been objectively demonstrated. The authors present a report of a man with experiential complex partial seizures reliably activated by thinking about his family home. During monitoring, such seizures were repeatedly induced in this way. Seizures were refractory to antiepileptic drugs, but ceased after left temporal resection. Pathologic examination showed cortical dysplasia.
Assuntos
Epilepsia Parcial Complexa/fisiopatologia , Reflexo , Pensamento , Adulto , Eletroencefalografia , Epilepsia Parcial Complexa/diagnóstico , Humanos , Masculino , VoliçãoRESUMO
BACKGROUND: Periodic paralysis is a well known complication of thytotoxicosis in Chinese and Japanese patients, but has been considered extremely rare in caucasians. PATIENTS AND METHODS: Between 1991 and 1996, we admitted 8 caucasian patients to our Hospital due to thyrotoxic periodic paralysis. We retrospectively analysed their clinical manifestations. RESULTS: All the patients were males. Their attacks started at night or early after awakening, frequently triggered by a high carbohydrate diet and physical exertion. Myalgias and flaccid weakness predominated over proximal leg muscles, sparing bulbar and respiratory musculature. Reflexes were brisk at the onset of the attack and reduced or absent during the course of the episode. Prior to diagnosis patients presented 1-5 attacks of thyrotoxic periodic paralysis each lasting 1-96 hours. Hypokalemia was documented in 6 patients. The episodes of periodic paralysis led to the diagnosis of a previously unsuspected thyrotoxicosis in 6 patients. In the other 2 patients the diagnosis of the thyroid dysfunction preceded the periodic paralysis. Attacks resolved after treatment of the hyperthyroid state. CONCLUSIONS: Thyrotoxic periodic paralysis is an under-diagnosed but probably frequent complication of hyperthyroidism in caucasians. Early recognition of the attacks is essential to investigate and treat the underlying thyroid dysfucntion whose symptoms are usually mild. The episodes of periodic paralysis resolve with the correction of the hyperthyroidism.
Assuntos
Paralisia/etiologia , Tireotoxicose/complicações , Tireotoxicose/fisiopatologia , Adulto , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Ischemic optic neuropathy, is an exceptional complication of surgery. Moreover, bilateral and simultaneous visual deficit in ischemic optic neuropathy is very rare. We describe two patients who suffered bilateral and simultaneous ischemic optic neuropathy after elective total hip replacement. Anemia and hypotension are the most likely risk factors.
Assuntos
Artroplastia de Quadril , Isquemia Encefálica/complicações , Doenças do Nervo Óptico/etiologia , Complicações Pós-Operatórias/patologia , Idoso , Isquemia Encefálica/patologia , Humanos , Masculino , Doenças do Nervo Óptico/patologia , Fatores de RiscoRESUMO
In order to search for early changes induced by the application of human immunoglobulin G (IgG) on motor nerve terminals, IgG from patients with amyotrophic lateral sclerosis (ALS) and control subjects was injected subcutaneously into the levator auris muscle of mice. A week or a month after the last injection, endplate potentials were recorded. No changes in quantal content of transmitter release were observed. In control and ALS IgG-treated muscles, neurotransmitter release remained sensitive to P/Q-type and insensitive to N-type voltage-sensitive calcium channel (VSCC) blockers as in untreated muscles. In contrast, IgG from 5 of 8 different ALS patients induced a significant reduction in quantal content of the evoked response after incubation with nitrendipine, indicating that a novel sensitivity to this calcium channel blocker appears in these motor nerve terminals. These results indicate that ALS IgG induces plastic changes at nerve terminals. The expression of transmitter release coupled to L-type VSCC indicate that ALS IgGs are capable of inducing plastic changes at the nerve terminals that may participate in the process leading to neuronal death.
Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo L/fisiologia , Imunoglobulina G/farmacologia , Doença dos Neurônios Motores/imunologia , Junção Neuromuscular/fisiologia , Adulto , Idoso , Animais , Potenciais Evocados/efeitos dos fármacos , Potenciais Evocados/fisiologia , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Camundongos , Pessoa de Meia-Idade , Músculo Esquelético/inervação , Junção Neuromuscular/efeitos dos fármacos , Junção Neuromuscular/imunologia , Nitrendipino/farmacologia , Valores de Referência , ômega-Agatoxina IVA/farmacologia , ômega-Conotoxina GVIA/farmacologiaRESUMO
The presence of inexcitable motor nerves early in the course of Guillain-Barré syndrome (GBS) identifies a subgroup of patients with more severe disease and delayed recovery. How frequently these electrodiagnostic findings reflect a primary axonal attack ("axonal" GBS) is controversial. We present two children with severe acute GBS, delayed recovery, and residual disability despite early treatment with human immunoglobulin. They had inexcitable motor nerves at days 6 and 7, and profuse fibrillations and positive waves on subsequent studies. Clinically and electrodiagnostically, both children's disease resembled the acute motor-sensory axonal variant of GBS (AMSAN). Sensory and motor nerve biopsies revealed severe macrophage-associated demyelination with axonal degeneration of variable severity. We conclude that clinical and electrodiagnostic features cannot discriminate between the "axonal" and demyelinating GBS. Early and severe demyelination with secondary axonal damage may mimic clinically and electrophysiologically the AMSAN variant of GBS.
Assuntos
Neurônios Motores/patologia , Nervo Fibular/patologia , Polirradiculoneuropatia/patologia , Nervo Sural/patologia , Biópsia , Criança , Eletromiografia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Microscopia EletrônicaRESUMO
Transmitter release evoked by nerve stimulation is highly dependent on Ca2+ entry through voltage-activated plasma membrane channels. Calcium influx may be modified in some neuromuscular diseases like Lambert-Eaton syndrome and amyotrophic lateral sclerosis. We studied the pharmacologic sensitivity of the transmitter release process to different calcium channel blockers in normal human muscles and found that funnel web toxin and omega-Agatoxin-IVA, both P-type calcium channel blockers, blocked nerve-elicited muscle action potentials and inhibited evoked synaptic transmission. The transmitter release was not affected either by nitrendipine, an L-type channel blocker, or omega-Conotoxin-GVIA, an N-type channel blocker. The pharmacologic profile of neuromuscular transmission observed in normal human muscles indicates that P-like channels mediate transmitter release at the motor nerve terminals.
Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/fisiologia , Junção Neuromuscular/fisiologia , Neurotransmissores/metabolismo , Potenciais de Ação/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Humanos , Músculos Intercostais , Junção Neuromuscular/efeitos dos fármacos , Nitrendipino/farmacologia , Peptídeos/farmacologia , Poliaminas/farmacologia , Valores de Referência , Músculos Respiratórios , Venenos de Aranha/farmacologia , Transmissão Sináptica/efeitos dos fármacos , Tubocurarina/farmacologia , ômega-Agatoxina IVA , ômega-Conotoxina GVIARESUMO
A 12-year-old developed a slowly progressive spastic gait at the age of 3. A marked loss of pain and temperature sensations led to a mutilating acropathy starting at age 5. Electrodiagnostic studies revealed a symmetric, axonal, predominantly sensory neuropathy, and magnetic resonance imaging ruled out compression of spinal cord. Sural nerve biopsy disclosed a predominant involvement of unmyelinated and a global loss of myelinated fibers, particularly larger ones. Clinical, electrodiagnostic and pathological findings of this case most likely represent an example of the "Cavanagh's variant", an unusual but distinct entity within the hereditary sensory and autonomic neuropathies.
Assuntos
Neuropatias Hereditárias Sensoriais e Autônomas/complicações , Paraparesia Espástica Tropical/complicações , Biópsia , Criança , Eletrodiagnóstico , Neuropatias Hereditárias Sensoriais e Autônomas/diagnóstico , Neuropatias Hereditárias Sensoriais e Autônomas/metabolismo , Humanos , Masculino , Nervo Sural/patologiaRESUMO
Thirteen children with severe Guillain-Barré syndrome were treated with human immune globulin. Patients received a mean total dose of 1.9 gm/kg of human immune globulin for 2 or 5 days. To evaluate the relationship between the response to human immune globulin and electrodiagnostic findings, we compared the clinical outcome of 3 groups of children. The first group consisted of 9 children with electrophysiologic evidence of a mean amplitude of the compound motor action potentials larger than 10% of the lower limit of normal. The second group of 4 children had inexcitable motor nerves. Children in the second group required longer periods to improve one functional grade (mean 67.3 days vs 18.8 days) and to reach grade 2 (219 days vs 32.7 days). Moreover, children in the second group were more disabled after 3 and 6 months, and they all remained with distal atrophy and weakness after 7 months of follow-up. Furthermore, the outcome of children in the second group was no different from that of a historic control of 5 untreated children with severe Guillain-Barré syndrome and similar electrophysiologic findings. Human immune globulin treatment in children with severe Guillain-Barré syndrome is safe, easy to administer, and does not increase the number of relapses. Nevertheless, it does not seem to benefit children with low mean compound motor action potential amplitude.
Assuntos
Imunização Passiva , Polirradiculoneuropatia/terapia , Criança , Progressão da Doença , Feminino , Humanos , Imunização Passiva/efeitos adversos , Masculino , Polirradiculoneuropatia/patologia , Prognóstico , Recidiva , Estudos Retrospectivos , Resultado do TratamentoAssuntos
Síndromes de Compressão Nervosa/etiologia , Nervo Sural/fisiopatologia , Potenciais de Ação , Adulto , Criança , Eletrodiagnóstico , Feminino , Humanos , Masculino , Síndromes de Compressão Nervosa/diagnóstico , Síndromes de Compressão Nervosa/fisiopatologia , Condução Nervosa , Neurônios Aferentes/fisiologia , Pressão , Remissão Espontânea , Nervo Sural/anatomia & histologiaRESUMO
We identified 5 of 44 consecutive children (11%) with Guillain-Barré syndrome who had electrophysiologic evidence of severe reduction of the mean amplitude of the compound motor action potentials (mean CMAP amplitude < 10% of lower limit of normal). EMG studies revealed profuse fibrillation activity in distal and proximal muscles after 2 weeks of onset. We compared this group with 16 consecutive children with GBS prospectively evaluated over 1 year, all of whom presented a mean CMAP amplitude > 10% of lower limit of normal. Children in the first group were more likely to require assisted ventilation (60% vs. 6.2%) and were more frequently quadriplegic at the peak of their disability (80% vs. 18.7%). They also required longer periods to improve one functional grade (mean 63.6 days vs. 16.6 days) and to become ambulatory (mean 156 days vs. 17.6 days). Moreover, only the children in the first group had distal atrophy of four limbs after 1 year of follow-up. Severe reduction of the mean amplitude of the CMAPs in children with GBS identifies a subgroup of patients with axonal damage that produces more severe weakness and delayed recovery.