Peripherally-derived LGI1-reactive monoclonal antibodies cause epileptic seizures in vivo.

One striking clinical hallmark in patients with autoantibodies to leucine-rich glioma inactivated 1 (LGI1) is the very frequent focal seizure semiologies, including faciobrachial dystonic seizures (FBDS), in addition to the amnesia. Polyclonal serum IgGs have successfully modelled the cognitive changes in vivo but not seizures. Hence, it remains unclear whether LGI1-autoantibodies are sufficient to cause seizures. We tested this with the molecularly precise monoclonal antibodies directed against LGI1 [LGI1-monoclonal antibodies (mAbs)], derived from patient circulating B cells. These were directed towards both major domains of LGI1, leucine-rich repeat and epitempin repeat, and infused intracerebroventricularly over 7 days into juvenile male Wistar rats using osmotic pumps. Continuous wireless EEG was recorded from a depth electrode placed in hippocampal CA3 plus behavioural tests for memory and hyperexcitability were performed. Following infusion completion (Day 9), post-mortem brain slices were studied for antibody binding and effects on Kv1.1. The LGI1-mAbs bound most strongly in the hippocampal CA3 region and induced a significant reduction in Kv1.1 cluster number in this subfield. By comparison to control-Ab injected rats video-EEG analysis over 9 days revealed convulsive and non-convulsive seizure activity in rats infused with LGI1-mAbs, with a significant number of ictal events. Memory was not impaired in the novel object recognition test. Peripherally-derived human LGI1-mAbs infused into rodent CSF provide strong evidence of direct in vivo epileptogenesis with molecular correlations. These findings fulfill criteria for LGI1-antibodies in seizure causation.

MyD88-mediated signaling is critical for the generation of seizure responses and cognitive impairment in a model of anti-N-methyl-D-aspartate receptor encephalitis.

OBJECTIVE: We previously demonstrated that interleukin-1 receptor-mediated immune activation contributes to seizure severity and memory loss in anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. In the present study, we assessed the role of the myeloid differentiation primary response gene 88 (MyD88), an adaptor protein in Toll-like receptor signaling, in the key phenotypic characteristics of anti-NMDAR encephalitis. METHODS: Monoclonal anti-NMDAR antibodies or control antibodies were infused into the lateral ventricle of MyD88 knockout mice (MyD88-/-) and control C56BL/6J mice (wild type [WT]) via osmotic minipumps for 2 weeks. Seizure responses were measured by electroencephalography. Upon completion of the infusion, the motor, anxiety, and memory functions of the mice were assessed. Astrocytic (glial fibrillary acidic protein [GFAP]) and microglial (ionized calcium-binding adaptor molecule 1 [Iba-1]) activation and transcriptional activation for the principal inflammatory mediators involved in seizures were determined using immunohistochemistry and quantitative real-time polymerase chain reaction, respectively. RESULTS: As shown before, 80% of WT mice infused with anti-NMDAR antibodies (n = 10) developed seizures (median = 11, interquartile range [IQR] = 3-25 in 2 weeks). In contrast, only three of 14 MyD88-/- mice (21.4%) had seizures (0, IQR = 0-.25, p = .01). The WT mice treated with antibodies also developed memory loss in the novel object recognition test, whereas such memory deficits were not apparent in MyD88-/- mice treated with anti-NMDAR antibodies (p = .03) or control antibodies (p = .04). Furthermore, in contrast to the WT mice exposed to anti-NMDAR antibodies, the MyD88-/- mice had a significantly lower induction of chemokine (C-C motif) ligand 2 (CCL2) in the hippocampus (p = .0001, Sidak tests). There were no significant changes in the expression of GFAP and Iba-1 in the MyD88-/- mice treated with anti-NMDAR or control antibodies. SIGNIFICANCE: These findings suggest that MyD88-mediated signaling contributes to the seizure and memory phenotype in anti-NMDAR encephalitis and that CCL2 activation may participate in the expression of these features. The removal of MyD88 inflammation may be protective and therapeutically relevant.

[Clinical characteristics of seizure-predominant autoimmune encephalitis and utility of anti-neuronal antibody scores for early treatment].

We analyzed 20 patients diagnosed with autoimmune neurological diseases with seizure predominance. In these patients, we examined the usefulness of Antibody Prevalence in Epilepsy and Encephalopathy (APE2) score and Antibodies Contributing to Focal Epilepsy Signs and Symptoms (ACES) score in autoimmune encephalitis (AE) for facilitating early treatment. APE2 score was positive in 19 of 20 patients. ACES score was positive in 15 of 20 patients, and 4 of 5 of the patients with negative ACES score did not have AE. Comprehensive assessment including the use of the above scores is desirable in the early stage of AE.

Risk of Seizure Recurrence Due to Autoimmune Encephalitis With NMDAR, LGI1, CASPR2, and GABABR Antibodies: Implications for Return to Driving.

BACKGROUND AND OBJECTIVES: Patients with ongoing seizures are usually not allowed to drive. The prognosis for seizure freedom is favorable in patients with autoimmune encephalitis (AIE) with antibodies against NMDA receptor (NMDAR), leucine-rich glioma-inactivated 1 (LGI1), contactin-associated protein-like 2 (CASPR2), and the gamma-aminobutyric-acid B receptor (GABABR). We hypothesized that after a seizure-free period of 3 months, patients with AIE have a seizure recurrence risk of <20% during the subsequent 12 months. This would render them eligible for noncommercial driving according to driving regulations in several countries. METHODS: This retrospective multicenter cohort study analyzed follow-up data from patients aged 15 years or older with seizures resulting from NMDAR-, LGI1-, CASPR2-, or GABABR-AIE, who had been seizure-free for ≥3 months. We used Kaplan-Meier (KM) estimates for the seizure recurrence risk at 12 months for each antibody group and tested for the effects of potential covariates with regression models. RESULTS: We included 383 patients with NMDAR-, 440 with LGI1-, 114 with CASPR2-, and 44 with GABABR-AIE from 14 international centers. After being seizure-free for 3 months after an initial seizure period, we calculated the probability of remaining seizure-free for another 12 months (KM estimate) as 0.89 (95% confidence interval [CI] 0.85-0.92) for NMDAR, 0.84 (CI 0.80-0.88) for LGI1, 0.82 (CI 0.75-0.90) for CASPR2, and 0.76 (CI 0.62-0.93) for GABABR. DISCUSSION: Taking a <20% recurrence risk within 12 months as sufficient, patients with NMDAR-AIE and LGI1-AIE could be considered eligible for noncommercial driving after having been seizure-free for 3 months.

Autoimmune-associated seizure disorders.

With the discovery of an expanding number of neural autoantibodies, autoimmune etiologies of seizures have been increasingly recognized. Clinical phenotypes have been identified in association with specific underlying antibodies, allowing an earlier diagnosis. These phenotypes include faciobrachial dystonic seizures with LGI1 encephalitis, neuropsychiatric presentations associated with movement disorders and seizures in NMDA-receptor encephalitis, and chronic temporal lobe epilepsy in GAD65 neurologic autoimmunity. Prompt recognition of these disorders is important, as some of them are highly responsive to immunotherapy. The response to immunotherapy is highest in patients with encephalitis secondary to antibodies targeting cell surface synaptic antigens. However, the response is less effective in conditions involving antibodies binding intracellular antigens or in Rasmussen syndrome, which are predominantly mediated by cytotoxic T-cell processes that are associated with irreversible cellular destruction. Autoimmune encephalitides also may have a paraneoplastic etiology, further emphasizing the importance of recognizing these disorders. Finally, autoimmune processes and responses to novel immunotherapies have been reported in new-onset refractory status epilepticus (NORSE) and febrile infection-related epilepsy syndrome (FIRES), warranting their inclusion in any current review of autoimmune-associated seizure disorders.

Autoinmunidad, convulsiones y epilepsia: breve revisión sistemática / Autoimmunity, seizures and epilepsy: a brief systematic review

INTRODUCCIÓN: La epilepsia es un desorden neurológico crónico caracterizado por crisis convulsivas recurrentes, y constituye uno de los trastornos neurológicos con mayor prevalencia global. Una de las etiologías que ha cobrado mayor relevancia en el último tiempo es la autoinmunidad, la que ha venido a dar explicación a muchos casos de epilepsia idiopática o refractaria a tratamientos convencionales. MÉTODOS: Se realizó una búsqueda avanzada asociada a filtros en la plataforma PubMed con los términos "epilepsy" y "autoimmunity". Se seleccionaron 17 artículos de un total de 98 publicados desde el año 2010 en adelante, y que aportaban mas datos desde la fisiopatología. RESULTADOS: En base a la literatura, se describen los principales mecanismos de autoinmunidad que generan epilepsia entre los destacan generación de auto-anticuerpos, desregulación del perfil de citoquinas y pérdida del control de linfocitos T autorreactivos, fenómenos que redundan en neuroinflamación y que se originan en el contexto de infecciones, síndromes paraneoplásicos, autoinmunidad materna transferida a hijos, encefalitis autoinmune, entre otras. CONCLUSIONES: En los últimos años ha habido grandes avances en la comprensión de la epilepsia autoinmune, sin embargo, aún queda mucho por comprender. Pese a lo prometedor que es el descubrimiento de anticuerpos, existen muchos casos de epilepsia con seronegatividad, o casos con la presencia de anticuerpos, pero no la epilepsia autoinmune. Cabe destacar que se debe precisar mecanismos diagnósticos eficaces y específicos que permitan generar protocolos terapéuticos atingentes y resolutivos.

Epilepsy is a neurological chronic disorder which is characterized by recurrent seizures and constitutes one of the most prevalent neurological disorders worldwide. One of the etiologies that has gained a lot of strength is autoimmunity, which has explained a lot of cases of idiopathic epilepsy or epilepsies refractory to common treatment. METHODS: An advanced search was made in the PubMed platform using filters with the terms "epilepsy" and "autoimmunity", showing 98 publications from 2010 onwards, leaving only 17 selected articles because of their pathophysiological information. RESULTS: Based on the literature, we described the main mechanisms of autoimmunity as a cause of epilepsy, standing out the ones related to auto-antibodies production, cytokines disregulation and autoreactive T lymphocytes control alteration, phenomenons related to neuroinflammation that arise from the context of infections, paraneoplastic syndromes, maternal autoimmunity transmitted to their babies, autoimmune encephalitis, etc. CONCLUSIONS: Great advances has been made on the understanding of autoimmune epilepsy in the last years, but despite this there's a lot that we need to comprehend. Although how promising was the discovery of antibodies there's still a lot of seronegative cases or cases with antibodies but without the epilepsy. It is worth mentioning that it becomes necessary to establish efficient and specific diagnostic mechanisms that allow us to create suitable and resolutive therapeutic protocols.

Encefalitis autoinmune por anticuerpos contra el receptor GABA-A: caso clínico / Autoimmune encephalitis induced by antibodies against GABA-A receptor

Among autoimmune encephalitides, a prevalent group are those associated with antibodies against the N-Methyl-D-aspartate receptor, which present with behavior abnormalities, psychosis, seizures and abnormal movements. A new variant, mediated by antibodies against the GABA-A receptor, was recen­tly described. We report a 66-years-old female with this form of encephalitis whose main manifestation was the presence of severe seizures leading to status epilepticus. The patient had a good response to immunomodulatory therapy with intravenous methylprednisolone, azathioprine and anticonvulsants. The laboratory tests initially detected anti-thyroid peroxidase antibodies which lead to the misdiagnosis of Hashimoto Encephalitis, which was ruled out after the detection of antibodies against GABA-A receptor. No malignancy was detected.

Absenteísmo-doença no serviço público municipal de Goiânia / Sickness absence in a municipal public service of Goiânia, Brazil

INTRODUÇÃO: O absenteísmo-doença, enquanto falta ao trabalho justificada por licença médica, é um importante indicador das condições de saúde dos trabalhadores. Em geral, características sociodemográficas e ocupacionais situam-se entre os principais fatores associados ao absenteísmo-doença. A administração pública é responsável por 21,8% dos empregos formais no Brasil. Esta população permite o estudo de uma grande variedade de categorias profissionais. OBJETIVO: Analisar o perfil e os indicadores de absenteísmo-doença entre servidores municipais de Goiânia, no Estado de Goiás, Brasil. Métodos: Estudo transversal das licenças certificadas para tratamento de saúde superiores a três dias, de todos os servidores, desde janeiro de 2005 a dezembro de 2010. Foram calculadas as prevalências, utilizando como critérios o número de indivíduos, os episódios e os dias de afastamento. RESULTADOS: Foram concedidas 40.578 licenças certificadas para tratamento de saúde a 13.408 servidores numa população média anual de 17.270 pessoas, o que resultou em 944.722 dias de absenteísmo. A prevalência acumulada de licença no período foi de 143,7%, com média anual de 39,2% e duração de 23 dias por episódio. A prevalência acumulada de absenteísmo-doença foi maior entre mulheres (52,0%) com idade superior a 40 anos (55,9%), com companheiro (49,9%), de baixa escolaridade (54,4%), profissionais de educação (54,7%), > 10 anos de serviço (61,9%) e múltiplos vínculos profissionais (53,7%). Os grupos de diagnósticos (CID-10) com as maiores prevalências acumuladas de licenças foram os do capítulo de transtornos mentais (26,5%), doenças osteomusculares (25,1%) e lesões (23,6%). CONCLUSÕES: Os indicadores de absenteísmo-doença expressam a magnitude desse fenômeno no serviço público e podem auxiliar no planejamento das ações de saúde do trabalhador, priorizando os grupos ocupacionais mais vulneráveis. .

BACKGROUND: Sickness absence, as work absenteeism justified by medical certificate, is an important health status indicator of the employees and, overall, sociodemographic and occupational characteristics are among the main factors associated with sickness absence. Public administration accounts for 21.8% of the formal job positions in Brazil. This population allows the study of a wide range of professional categories. OBJECTIVE: To assess the profile and indicators of sickness absence among public workers from the municipality of Goiania, in the State of Goiás, Brazil. METHODS: A cross-sectional study on certified sick leaves, lasting longer than three days, of all civil servants from January 2005 to December 2010. Prevalence rates were calculated using as main criteria the number of individuals, episodes and sick days. RESULTS: 40,578 certified sick leaves were granted for health treatment among 13,408 public workers, in an annual average population of 17,270 people, which resulted in 944,722 days of absenteeism. The cumulative prevalence of sick leave for the period was of 143.7%, with annual average of 39.2% and duration of 23 days per episode. The cumulative prevalence of sickness absence was higher among women (52.0%), older than 40 years old (55.9%), with a partner (49.9%), low schooling (54.4%), education professionals (54.7%), > 10 years of service (61.9%), and with multiple work contracts (53.7%). Diagnoses groups (ICD-10) with higher cumulative prevalence of sick leaves were those with mental disorders (26.5%), musculoskeletal diseases (25.1%), and injuries (23.6%). CONCLUSIONS: Indicators of sickness absence express the magnitude of this phenomenon in the public sector and can assist in planning health actions for the worker, prioritizing the most vulnerable occupational groups. .