Subthalamic low beta bursts differ in Parkinson's disease phenotypes.

OBJECTIVE: Parkinson's disease (PD) patients may be categorized into tremor-dominant (TD) and postural-instability and gait disorder (PIGD) motor phenotypes, but the dynamical aspects of subthalamic nucleus local field potentials (STN-LFP) and the neural correlates of this phenotypical classification remain unclear. METHODS: 35 STN-LFP (20 PIGD and 15 TD) were investigated through continuous wavelet transform and machine-learning-based methods. The beta oscillation - the main band associated with motor impairment in PD - dynamics was characterized through beta burst parameters across phenotypes and burst intervals under specific proposed criteria for optimal burst threshold definition. RESULTS: Low-frequency (13-22 Hz) beta burst probability was the best predictor for PD phenotypes (75% accuracy). PIGD patients presented higher average burst duration (p = 0.018), while TD patients exhibited higher burst probability (p = 0.014). Categorization into shorter and longer than 400 ms bursts led to significant interaction between burst length categories and the phenotypes (p < 0.050) as revealed by mixed-effects models. Long burst durations and short bursts probability positively correlated, respectively, with rigidity-bradykinesia (p = 0.029) and tremor (p = 0.038) scores. CONCLUSIONS: Subthalamic low-frequency beta bursts differed between TD and PIGD phenotypes and correlated with motor symptoms. SIGNIFICANCE: These findings improve the PD phenotypes' electrophysiological characterization and may define new criteria for adaptive deep brain stimulation.

High prevalence of self-reported non-motor symptoms and lack of correlation with motor severity in adult patients with idiopathic isolated dystonia.

BACKGROUND: Although abnormal movements and postures are the hallmark of dystonia, non-motor symptoms (NMS) are common and negatively affect quality of life. OBJECTIVES: The aim of this study was to screen dystonia patients for NMS and analyze their association with clinical parameters, including motor disability. METHODS: Adult patients with idiopathic isolated dystonia were interviewed and examined. Dystonia severity was evaluated with the Fahn-Marsden Dystonia Rating Scale and the presence of NMS was assessed using a list of 29 complaints. RESULTS: A hundred and two patients (63.7% female) were enrolled. Dystonia began after 20 years of age in 61.8% and was focal or segmental in 82.8% of patients. Only eight patients (7.8%) had no NMS and 59.8% reported more than five. The most prevalent NMS were pain (72.5%) and anxiety (63.7%), followed by difficulty recalling information (44.1%), sadness/anhedonia (41.2%), and difficulty falling asleep (38.2%). No correlation was found between the total number of NMS and dystonia severity (p = 0.18) or regular botulinum toxin use (p = 0.66). The majority of NMS domains correlated with each other. CONCLUSIONS: Our results confirm a high prevalence of NMS among dystonia patients, even in those with mild motor disability. The pathophysiology of NMS in dystonia remains to be completely understood.

Electroencephalographic findings among inpatients with COVID-19 in a tertiary hospital from a middle-income country.

BACKGROUND: In 2019, the world witnessed the emergence of a new type of coronavirus - the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The spectrum of coronavirus disease 2019 (COVID-19) is variable, and amongst its manifestations are neurological implications. OBJECTIVE: This report aimed to describe electroencephalographic findings in COVID-19 patients from a general tertiary hospital in São Paulo, Brazil. METHODS: It was a retrospective, observational, and non-interventional study. Data were collected anonymously, comprising inpatients from Mar 1 to Jun 30, 2020, either confirmed (positive RT-PCR) or probable cases (CO-RADS 4/5) who had performed EEG during hospitalization. RESULTS: Twenty-eight patients were enrolled, 17 (60.7%) women and 11 men, with a median age of 58 (minimum and maximum: 18-86; IQR 23.5). COVID-19 diagnosis was confirmed in 22 (78.5%). Twenty-one patients (75%) had severe disease, requiring mechanical ventilation due to acute respiratory distress syndrome (ARDS); 16 (57.1%) patients developed adjunct sepsis throughout hospitalization. There was no specific pattern found for COVID-19 in EEG. No patients presented with status epilepticus or electrographic events; most patients developed an encephalopathic pattern, as seen in most studies, with a high prevalence of altered mental status as an indication for EEG. Adjunct sepsis was associated with higher mortality. CONCLUSIONS: EEG presents as a useful tool in the context of COVID-19, as in other conditions, to differentiate nonconvulsive status epilepticus (NCSE) from encephalopathy and other causes of mental status alterations. Further studies are required to analyze whether there might be a specific EEG pattern to the disease.

Fields of Forel Brain Stimulation Improves Levodopa-Unresponsive Gait and Balance Disorders in Parkinson's Disease.

BACKGROUND: Gait and balance disturbance are challenging symptoms in advanced Parkinson's disease (PD). Anatomic and clinical data suggest that the fields of Forel may be a potential surgical target to treat these symptoms. OBJECTIVE: To test whether bilateral stimulation centered at the fields of Forel improves levodopa unresponsive freezing of gait (FOG), balance problems, postural instability, and falls in PD. METHODS: A total of 13 patients with levodopa-unresponsive gait disturbance (Hoehn and Yahr stage ≥3) were included. Patients were evaluated before (on-medication condition) and 1 yr after surgery (on-medication-on-stimulation condition). Motor symptoms and quality of life were assessed with the Unified Parkinson's Disease Rating scale (UPDRS III) and Quality of Life scale (PDQ-39). Clinical and instrumented analyses assessed gait, balance, postural instability, and falls. RESULTS: Surgery improved balance by 43% (95% confidence interval [CI]: 21.2-36.4 to 35.2-47.1; P = .0012), reduced FOG by 35% (95% CI: 15.1-20.3 to 8.1-15.3; P = .0021), and the monthly number of falls by 82.2% (95% CI: 2.2-6.9 to -0.2-1.7; P = .0039). Anticipatory postural adjustments, velocity to turn, and postural sway measurements also improved 1 yr after deep brain stimulation (DBS). UPDRS III motor scores were reduced by 27.2% postoperatively (95% CI: 42.6-54.3 to 30.2-40.5; P < .0001). Quality of life improved 27.5% (95% CI: 34.6-48.8 to 22.4-37.9; P = .0100). CONCLUSION: Our results suggest that DBS of the fields of Forel improved motor symptoms in PD, as well as the FOG, falls, balance, postural instability, and quality of life.

Electroencephalographic findings among inpatients with COVID-19 in a tertiary hospital from a middle-income country / Achados eletroencefalográficos entre pacientes internados com COVID-19 em um hospital terciário de um país em desenvolvimento

ABSTRACT Background: In 2019, the world witnessed the emergence of a new type of coronavirus - the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The spectrum of coronavirus disease 2019 (COVID-19) is variable, and amongst its manifestations are neurological implications. Objective: This report aimed to describe electroencephalographic findings in COVID-19 patients from a general tertiary hospital in São Paulo, Brazil. Methods: It was a retrospective, observational, and non-interventional study. Data were collected anonymously, comprising inpatients from Mar 1 to Jun 30, 2020, either confirmed (positive RT-PCR) or probable cases (CO-RADS 4/5) who had performed EEG during hospitalization. Results: Twenty-eight patients were enrolled, 17 (60.7%) women and 11 men, with a median age of 58 (minimum and maximum: 18-86; IQR 23.5). COVID-19 diagnosis was confirmed in 22 (78.5%). Twenty-one patients (75%) had severe disease, requiring mechanical ventilation due to acute respiratory distress syndrome (ARDS); 16 (57.1%) patients developed adjunct sepsis throughout hospitalization. There was no specific pattern found for COVID-19 in EEG. No patients presented with status epilepticus or electrographic events; most patients developed an encephalopathic pattern, as seen in most studies, with a high prevalence of altered mental status as an indication for EEG. Adjunct sepsis was associated with higher mortality. Conclusions: EEG presents as a useful tool in the context of COVID-19, as in other conditions, to differentiate nonconvulsive status epilepticus (NCSE) from encephalopathy and other causes of mental status alterations. Further studies are required to analyze whether there might be a specific EEG pattern to the disease.

RESUMO Antecedentes: Em 2019, testemunhou-se o surgimento de um novo tipo de coronavírus - o coronavírus associado à síndrome da angústia respiratória tipo 2 (SARS-CoV-2). O espectro da doença associada ao novo coronavírus, a COVID-19, é variável e, dentre suas manifestações, há implicações neurológicas. Objetivos: O presente estudo objetivou descrever achados eletroencefalográficos em pacientes com COVID-19 internados em um hospital terciário em São Paulo. Métodos: Tratou-se de estudo observacional, retrospectivo e não-intervencionista, realizado por meio de coleta anônima e retrospectiva de dados de prontuário médico de pacientes com diagnóstico confirmado (RT-PCR positivo) ou provável (CO-RADS 4 ou 5), que realizaram eletroencefalograma durante internação hospitalar. Resultados: Vinte e oito pacientes foram elencados, 17 (60,7%) mulheres e 11 homens. O diagnóstico de COVID-19 foi confirmado em 22 (78,5%) dos casos. Dos pacientes, 21 (75%) apresentaram a doença, requerendo suporte ventilatório, e 16 (57,1%) desenvolveram sepse sobreposta. Não houve padrão específico de EEG para COVID-19, e nenhum paciente apresentou estado de mal epiléptico ou crise eletrográfica; a maioria desenvolveu padrão de encefalopatia, com alentecimento da atividade cerebral, sendo a alta prevalência de alteração de estado mental a indicação para o exame. A sepse sobreposta foi associada a um pior desfecho, com maior mortalidade. Conclusão: No contexto da COVID-19, o EEG figura como ferramenta importante, auxiliando, como em outras condições, na diferenciação entre estado de mal epiléptico, encefalopatia e outras causas de alteração do estado mental. Estudos adicionais são necessários para avaliar a existência de padrão específico de alteração eletroencefalográfica na COVID-19.

Acute Disseminated Encephalomyelitis in COVID-19: presentation of two cases and review of the literature.

BACKGROUND: Neurological manifestations of COVID-19 are still incompletely understood. Neurological manifestations may be due to direct viral effect on neurons and glial cells, to an immune-mediated response to the virus, or to a hypercoagulable state and associated endothelial damage, as well as to severe systemic disease with prolonged intensive care unit stay. OBJECTIVE: To describe two patients with severe SARS-CoV-2 infection and delayed recovery of consciousness after sedation withdrawal, in whom MRI disclosed multifocal white matter brain lesions, compatible with the diagnosis of acute disseminated encephalomyelitis. METHODS: Observational report of two cases of severe COVID-19 infection in patients from two tertiary hospitals in São Paulo, Brazil. RESULTS: These patients underwent neurologic and systemic evaluation for delayed awakening after sedation withdrawal. MRI displayed multifocal centrum semiovale lesions, suggestive of demyelinating inflammation. Cerebrospinal fluid (CSF) polymerase chain reaction (PCR) for SARS-CoV-2 was negative in both cases. CONCLUSION: A recurrent pattern of multifocal white matter lesions can occur in COVID-19 patients, possibly associated with delayed awakening. Additional studies are necessary to elucidate the role of the viral infection and of inflammatory and immune-mediated associated changes in neurological manifestations of COVID-19.

Rasmussen encephalitis: an older adult presentation?

Rasmussen encephalitis (RE) is a classic disorder in the child age group, and only 10% of cases are described in adults. We bring two proven cases of RE in older adults aged over 55 years. OBJECTIVE: To describe the clinical characteristics, progression, diagnostic assessment, neuropathological findings, and treatment of RE in two clinical cases of patients over 55 years of age. Furthermore, we address progressive cognitive decline as an important feature of the RE presentation in older adults in association with focal epilepsy. METHODS: This is a case series from two tertiary hospitals from São Paulo - Brazil. Retrospective data were collected from one case. Results: Two male individuals aged >55 years with clinical presentation of focal epilepsy along with progressive cognitive deterioration. CONCLUSIONS: RE could be considered the cause of progressive cognitive decline in older adults, especially if focal epilepsy is described together with asymmetrical neuroimaging findings.

A encefalite de Rasmussen (ER) é um distúrbio clássico da faixa etária infantil e apenas 10% dos casos são descritos em adultos. Trazemos dois casos comprovados de ER em idosos, com idade acima de 55 anos de idade. OBJETIVO: Descrever as características clínicas, evolução, avaliação diagnóstica, achados neuropatológicos e tratamento da ER em dois casos clínicos com mais de 55 anos de idade. Além disso, atentar para o declínio cognitivo progressivo como uma característica importante na apresentação ER idosos em associação à epilepsia focal. MÉTODOS: Série de casos de dois Hospitais Terciários em São Paulo, Brasil. Dados retrospectivos foram coletados de um caso. RESULTADOS: Dois indivíduos do sexo masculino com idade >55 anos e apresentação clínica de epilepsia focal associada a deterioração cognitiva progressiva. CONCLUSÃO: A ER pode ser considerada a causa do declínio cognitivo progressivo em idosos, especialmente se for descrita epilepsia focal associada a achados assimétricos em neuroimagem.

Acute Disseminated Encephalomyelitis in COVID-19: presentation of two cases and review of the literature / Encefalomielite disseminada aguda associada a COVID-19: relato de dois casos e revisão de literatura

ABSTRACT Background: Neurological manifestations of COVID-19 are still incompletely understood. Neurological manifestations may be due to direct viral effect on neurons and glial cells, to an immune-mediated response to the virus, or to a hypercoagulable state and associated endothelial damage, as well as to severe systemic disease with prolonged intensive care unit stay. Objective: To describe two patients with severe SARS-CoV-2 infection and delayed recovery of consciousness after sedation withdrawal, in whom MRI disclosed multifocal white matter brain lesions, compatible with the diagnosis of acute disseminated encephalomyelitis. Methods: Observational report of two cases of severe COVID-19 infection in patients from two tertiary hospitals in São Paulo, Brazil. Results: These patients underwent neurologic and systemic evaluation for delayed awakening after sedation withdrawal. MRI displayed multifocal centrum semiovale lesions, suggestive of demyelinating inflammation. Cerebrospinal fluid (CSF) polymerase chain reaction (PCR) for SARS-CoV-2 was negative in both cases. Conclusion: A recurrent pattern of multifocal white matter lesions can occur in COVID-19 patients, possibly associated with delayed awakening. Additional studies are necessary to elucidate the role of the viral infection and of inflammatory and immune-mediated associated changes in neurological manifestations of COVID-19.

RESUMO Introdução: As manifestações neurológicas causadas pela COVID-19 ainda não estão completamente elucidadas. O comprometimento neurológico pode decorrer de um efeito viral direto em neurônios ou em células gliais, a efeito imunomediado em resposta à infecção viral, ou de um efeito secundário a estados de hipercoagulabilidade e danos endoteliais, assim como decorrente de complicações sistêmicas graves relacionadas a cuidados intensivos prolongados na unidade de terapia intensiva. Objetivo: Descrever dois pacientes com recuperação tardia do nível de consciência após a retirada da sedação associados à infecção grave pelo SARS-CoV-2, que apresentaram lesões multifocais de substância branca, compatíveis com o diagnóstico de encefalomielite disseminada aguda. Métodos: Estudo observacional, com relato de dois casos de infecção grave pela COVID-19, em dois hospitais terciários na cidade de São Paulo, Brasil. Resultados: Os pacientes foram submetidos à investigação sistêmica e neurológica para avaliação de estado alterado de consciência após retirada de sedação. A ressonância magnética de crânio evidenciou lesões multifocais no centro semioval, sugestivos de processo inflamatório desmielinizante. Análise liquórica evidenciou PCR negativo para SARS-CoV-2 em ambos os casos. Conclusão: Lesões multifocais de substância branca podem ocorrer em pacientes com COVID-19, possivelmente associadas a estados alterados de consciência. Estudos adicionais são necessários para determinar o processo fisiopatológico da infecção viral e dos estados inflamatórios e imunomediados na gênese das manifestações neurológicas causadas pela COVID-19.

Rasmussen encephalitis: an older adult presentation? / Encefalite de rasmussen: apresentação em idosos?

ABSTRACT. Rasmussen encephalitis (RE) is a classic disorder in the child age group, and only 10% of cases are described in adults. We bring two proven cases of RE in older adults aged over 55 years. Objective: To describe the clinical characteristics, progression, diagnostic assessment, neuropathological findings, and treatment of RE in two clinical cases of patients over 55 years of age. Furthermore, we address progressive cognitive decline as an important feature of the RE presentation in older adults in association with focal epilepsy. Methods: This is a case series from two tertiary hospitals from São Paulo - Brazil. Retrospective data were collected from one case. Results: Two male individuals aged >55 years with clinical presentation of focal epilepsy along with progressive cognitive deterioration. Conclusions: RE could be considered the cause of progressive cognitive decline in older adults, especially if focal epilepsy is described together with asymmetrical neuroimaging findings.

RESUMO. A encefalite de Rasmussen (ER) é um distúrbio clássico da faixa etária infantil e apenas 10% dos casos são descritos em adultos. Trazemos dois casos comprovados de ER em idosos, com idade acima de 55 anos de idade. Objetivo: Descrever as características clínicas, evolução, avaliação diagnóstica, achados neuropatológicos e tratamento da ER em dois casos clínicos com mais de 55 anos de idade. Além disso, atentar para o declínio cognitivo progressivo como uma característica importante na apresentação ER idosos em associação à epilepsia focal. Métodos: Série de casos de dois Hospitais Terciários em São Paulo, Brasil. Dados retrospectivos foram coletados de um caso. Resultados: Dois indivíduos do sexo masculino com idade >55 anos e apresentação clínica de epilepsia focal associada a deterioração cognitiva progressiva. Conclusão: A ER pode ser considerada a causa do declínio cognitivo progressivo em idosos, especialmente se for descrita epilepsia focal associada a achados assimétricos em neuroimagem.

Myasthenia Gravis Related to Thymic Carcinoma: A Case Study.

Myasthenia gravis and thymoma are often presented in association with ∼10% of myasthenic cases having concomitant thymoma. Thymic carcinoma is one of the rarest/aggressive human epithelial tumors and has no correlation with myasthenia gravis hitherto. Here is provided a clinical case and review of literature on a very rare association of thymic carcinoma (with no sign of thymoma) and myasthenia gravis (antiacetylcholine receptor antibody positive). Two years after thymectomy, clinical evolution was satisfactory. This clinical case elicits hypothesis that thymic carcinoma may be related with myasthenia gravis, what may have good prognostic from oncologic and neurologic perspectives.

The prevalence of PRKRA mutations in idiopathic dystonia.

INTRODUCTION: DYT-PRKRA (DYT16) is considered a rare cause of dystonia-parkinsonism. The significance of this gene as a cause of dystonia and its phenotypical characterization must be determined in larger cohorts. We aimed to investigate the role of PRKRA in patients with dystonia. METHODS: We sequenced PRKRA in 153 unrelated Brazilian patients with idiopathic dystonia. The frequency of novel missense variants was investigated in healthy Brazilian controls and in public databases. Homozygosity in the PRKRA region was assessed through polymorphic markers. RESULTS: PRKRA variants were identified in seven probands with isolated dystonia, including a novel c.C795A variant in compound heterozygosity with the previously described c.C665T variant. Heterozygosity in the gene region was observed in two probands who were homozygous for c.C665T, indicating that this mutation originated from independent events, suggesting a hotspot. CONCLUSION: PRKRA is not an unusual cause of idiopathic dystonia. In this cohort, it was responsible for 4.5% of the total of cases (4.9% of the isolated dystonia cases). The most common phenotype was early-onset isolated focal dystonia followed by generalization, parkinsonism was not observed. This is first report of PRKRA causing adulthood-onset dystonia. Screenings of large cohorts are recommended to investigate the role of this gene in isolated dystonia, as well as in dystonia-parkinsonism cases worldwide.

Catatonia, beyond a psychiatric syndrome.

Although catatonia is a well-known psychiatric syndrome, there are many possible systemic and neurological etiologies. The aim of this case report was to present a case of a patient with cerebral venous sinus thrombosis and infarction in which catatonia was the clinical manifestation of a possible nonconvulsive status epilepticus. To our knowledge, only one such case has been reported in the literature, which had a simplified diagnostic investigation. It is important to correctly recognize the organic cause underlying catatonia in order to treat the patient as soon as possible thereby improving outcome. Therefore, physicians need to update their knowledge on catatonia, recognizing that it can be part of a psychiatric or neurologic condition.

Embora a catatonia seja uma síndrome psiquiátrica bem conhecida, existem várias etiologias possíveis, tanto sistêmicas quanto neurológicas. O objetivo deste relato de caso é apresentar um quadro de trombose venosa central com infarto venoso em que a catatonia foi a manifestação clínica de um possível status não convulsivo. Na concepção dos autores, apenas um caso é encontrado na literatura, porém com uma propedêutica simplificada. É importante o correto reconhecimento das causas orgânicas que podem estar causando a catatonia para que sejam corrigidas assim que possível, melhorando o prognóstico do paciente. Além disso, os médicos precisam atualizar seus conhecimentos sobre a catatonia, uma vez que ela pode ser parte tanto de uma condição psiquiátrica quanto neurológica.

Catatonia, beyond a psychiatric syndrome / Catatonia, além de uma síndrome psiquiátrica

ABSTRACT Although catatonia is a well-known psychiatric syndrome, there are many possible systemic and neurological etiologies. The aim of this case report was to present a case of a patient with cerebral venous sinus thrombosis and infarction in which catatonia was the clinical manifestation of a possible nonconvulsive status epilepticus. To our knowledge, only one such case has been reported in the literature, which had a simplified diagnostic investigation. It is important to correctly recognize the organic cause underlying catatonia in order to treat the patient as soon as possible thereby improving outcome. Therefore, physicians need to update their knowledge on catatonia, recognizing that it can be part of a psychiatric or neurologic condition.

RESUMO Embora a catatonia seja uma síndrome psiquiátrica bem conhecida, existem várias etiologias possíveis, tanto sistêmicas quanto neurológicas. O objetivo deste relato de caso é apresentar um quadro de trombose venosa central com infarto venoso em que a catatonia foi a manifestação clínica de um possível status não convulsivo. Na concepção dos autores, apenas um caso é encontrado na literatura, porém com uma propedêutica simplificada. É importante o correto reconhecimento das causas orgânicas que podem estar causando a catatonia para que sejam corrigidas assim que possível, melhorando o prognóstico do paciente. Além disso, os médicos precisam atualizar seus conhecimentos sobre a catatonia, uma vez que ela pode ser parte tanto de uma condição psiquiátrica quanto neurológica.

Screening of GNAL variants in Brazilian patients with isolated dystonia reveals a novel mutation with partial loss of function.

GNAL was identified as a cause of dystonia in patients from North America, Europe and Asia. In this study, we aimed to investigate the prevalence of GNAL variants in Brazilian patients with dystonia. Ninety-one patients with isolated idiopathic dystonia, negative for THAP1 and TOR1A mutations, were screened for GNAL variants by Sanger sequencing. Functional characterization of the Gαolf protein variant was performed using the bioluminescence resonance energy transfer assay. A novel heterozygous nonsynonymous variant (p. F133L) was identified in a patient with cervical and laryngeal dystonia since the third decade of life, with no family history. This variant was not identified in healthy Brazilian controls and was not described in 63,000 exomas of the ExAC database. The F133L mutant exhibited significantly elevated levels of basal BRET and severely diminished amplitude of response elicited by dopamine, that both indicate substantial functional impairment of Gαolf in transducing receptor signals, which could be involved in dystonia pathophysiology. GNAL mutations are not a common cause of dystonia in the Brazilian population and have a lower prevalence than THAP1 and TOR1A mutations. We present a novel variant that results in partial Gαolf loss of function.

Clinical Implications of the National Institute of Neurological Disorders and Stroke Criteria for Diagnosing Psychosis in Parkinson's Disease.

The effect of psychotic symptoms in Parkinson's disease (PD) is variable among patients, and different methods to assess psychosis may yield conflicting results. A sample of 102 patients with a diagnosis of idiopathic PD underwent neurological, psychiatric, and neuropsychological assessment. Participants were divided into three groups: those who met DSM criteria for psychotic disorder, those who had psychotic symptoms but did not meet DSM criteria, and those without any psychotic symptoms. The first group had significantly worse sleep and worse cognitive and psychopathological symptoms compared with the other two groups. Results suggested that patients meeting DSM criteria for psychotic disorder comprise a separate clinical category.

Stiff-Person Syndrome and Graves' Disease: A Pediatric Case Report.

A 9-year-old female child presented with a history of falls, weight loss, diffuse leg pain, and progressive gait disorder, following 1 previous event described as a tonic-clonic seizure. She had increased thyroid volume, brisk symmetric reflexes, abnormal gait, and painful spasms of the paraspinal musculature. Thyroid function tests indicated biochemical hyperthyroidism, and thyrotropin receptor antibodies were positive. Her electromyography showed continuous activation of normal motor units of the paraspinal and proximal lower extremity muscles. The patient had a diagnosis of Graves' disease with associated stiff-person syndrome, with elevated anti-glutamic acid decarboxylase antibody levels. After intravenous immunoglobulin therapy, her ambulation was substantially improved and the symptoms of stiff-person syndrome decreased dramatically.

Central Nervous System Idiopathic Inflammatory Demyelinating Disorders in South Americans: A Descriptive, Multicenter, Cross-Sectional Study.

The idiopathic inflammatory demyelinating disease (IIDD) spectrum has been investigated among different populations, and the results have indicated a low relative frequency of neuromyelitis optica (NMO) among multiple sclerosis (MS) cases in whites (1.2%-1.5%), increasing in Mestizos (8%) and Africans (15.4%-27.5%) living in areas of low MS prevalence. South America (SA) was colonized by Europeans from the Iberian Peninsula, and their miscegenation with natives and Africans slaves resulted in significant racial mixing. The current study analyzed the IIDD spectrum in SA after accounting for the ethnic heterogeneity of its population. A cross-sectional multicenter study was performed. Only individuals followed in 2011 with a confirmed diagnosis of IIDD using new diagnostic criteria were considered eligible. Patients' demographic, clinical and laboratory data were collected. In all, 1,917 individuals from 22 MS centers were included (73.7% female, 63.0% white, 28.0% African, 7.0% Mestizo, and 0.2% Asian). The main disease categories and their associated frequencies were MS (76.9%), NMO (11.8%), other NMO syndromes (6.5%), CIS (3.5%), ADEM (1.0%), and acute encephalopathy (0.4%). Females predominated in all main categories. The white ethnicity also predominated, except in NMO. Except in ADEM, the disease onset occurred between 20 and 39 years old, early onset in 8.2% of all cases, and late onset occurred in 8.9%. The long-term morbidity after a mean disease time of 9.28±7.7 years was characterized by mild disability in all categories except in NMO, which was scored as moderate. Disease time among those with MS was positively correlated with the expanded disability status scale (EDSS) score (r=0.374; p=<0.001). This correlation was not observed in people with NMO or those with other NMO spectrum disorders (NMOSDs). Among patients with NMO, 83.2% showed a relapsing-remitting course, and 16.8% showed a monophasic course. The NMO-IgG antibody tested using indirect immunofluorescence (IIF) with a composite substrate of mouse tissues in 200 NMOSD cases was positive in people with NMO (95/162; 58.6%), longitudinally extensive transverse myelitis (10/30; 33.3%) and bilateral or recurrent optic neuritis (8/8; 100%). No association of NMO-IgG antibody positivity was found with gender, age at onset, ethnicity, early or late onset forms, disease course, or long-term severe disability. The relative frequency of NMO among relapsing-remitting MS (RRMS) + NMO cases in SA was 14.0%. Despite the high degree of miscegenation found in SA, MS affects three quarters of all patients with IIDD, mainly white young women who share similar clinical characteristics to those in Western populations in the northern hemisphere, with the exception of ethnicity; approximately one-third of all cases occur among non-white individuals. At the last assessment, the majority of RRMS patients showed mild disability, and the risk for secondary progression was significantly superior among those of African ethnicity. NMO comprises 11.8% of all IIDD cases in SA, affecting mostly young African-Brazilian women, evolving with a recurrent course and causing moderate or severe disability in both ethnic groups. The South-North gradient with increasing NMO and non-white individuals from Argentina, Paraguay, Brazil and Venezuela confirmed previous studies showing a higher frequency of NMO among non-white populations.