Intraoperative assessment of microimplantation-induced acute brain inflammation with titanium oxynitride-based plasmonic biosensor.

Implantable devices for brain-machine interfaces and managing neurological disorders have experienced rapid growth in recent years. Although functional implants offer significant benefits, issues related to transient trauma and long-term biocompatibility and safety are of significant concern. Acute inflammatory reaction in the brain tissue caused by microimplants is known to be an issue but remains poorly studied. This study presents the use of titanium oxynitride (TiNO) nanofilm with defined surface plasmon resonance (SPR) properties for point-of-care characterizing of acute inflammatory responses during robot-controlled micro-neuro-implantation. By leveraging surface-enriched oxynitride, TiNO nanofilms can be biomolecular-functionalized through silanization. This label-free TiNO-SPR biosensor exhibits a high sensitivity toward the inflammatory cytokine interleukin-6 with a detection limit down to 6.3 fg ml-1 and a short assay time of 25 min. Additionally, intraoperative monitoring of acute inflammatory responses during microelectrode implantation in the mice brain has been accomplished using the TiNO-SPR biosensors. Through intraoperative cerebrospinal fluid sampling and point-of-care plasmonic biosensing, the rhythm of acute inflammatory responses induced by the robot-controlled brain microelectrodes implantation has been successfully depicted, offering insights into intraoperative safety assessment of invasive brain-machine interfaces.

Anti-Yo antibody-associated Autoimmune Encephalitis due to Breast Adenocarcinoma in a male patient.

Paraneoplastic neurological syndromes occur due to immune-mediated neuronal dysfunction secondary to systemic malignancy, and symptoms can usually be seen before malignancy. There are many subtypes that depend on the antibodies present or the proteins they target. Accurate epidemiological data are lacking as it is difficult to diagnose. We would like to present a case of anti-Yo antibody-associated encephalitis due to breast cancer in a 47-year-old male patient. When we searched the literature, we did not find a case of anti-Yo-associated autoimmune encephalitis due to breast adenocarcinoma in a male patient. For this reason, we find it worth presenting our case.

Autoimmune encephalitis mediated by postvaccination and infection of SARS-CoV-2 in a patient with a narcolepsy type 1. / Encefalitis autoinmune tras vacunación e infección por el SARS-CoV-2 en un paciente con narcolepsia de tipo 1.

INTRODUCTION: We present a narcolepsy type 1 patient that develop an autoimmune encephalitis post vaccine and/or a SARS-CoV-2 infection. CASE REPORT: At 23 years old, the patient was referred to the emergency room with difficult speaking, headache and tremor followed by changes in behavior, autonomic dysfunction, right focal motor seizure and lethargy. He has received seven weeks before mRNA-1273 (Moderna) vaccine followed by a SARS-CoV-2 infection four weeks after vaccination (positive antigen test). RESULTS: The neurological examination was normal (visual fields, cranial nerves, motor, sensory and reflexes). Nasopharyngeal swab polymerase chain reaction (PCR) testing for COVID-19 was negative. Cerebrospinalfluid (CSF) had highly elevated protein and lymphocytic pleocytosis. CSF bacterial and fungal cultures for viral infections were negative. Brain magnetic resonance imaging (MRI) showed no abnormality on the non-enhanced sequences but the diffusion weighted imaging showed restricted diffusion with high signal on the left hemisphere mainly in the cerebral cortex with a gyro morphology, patched distribution with involvement of the temporal and frontal lobes. Chest, abdomen and pelvis computed tomography; pelvic and scrotum ultrasound, showed no malignancy. Onconeural antibodies were negative. The patient was treated with plasmapheresis and corticosteroids with a good clinical outcome and near complete resolution of the MRI abnormalities. CONCLUSION: The patient fulfilled the diagnostic criteria for autoimmune encephalitis with subacute onset. COVID-19 infection and vaccination could constitute a risk in a patient with narcolepsy as in this case and, could help to provide better understanding of the implication of immune-mediated processes in the pathophysiology of the diseases.

TITLE: Encefalitis autoinmune tras vacunación e infección por el SARS-CoV-2 en un paciente con narcolepsia de tipo 1.Introducción. Presentamos un paciente diagnosticado de narcolepsia de tipo 1 que desarrolló una encefalitis autoinmune posvacunal y/o tras una infección por el SARS-CoV-2. Caso clínico. Paciente de 23 años que es remitido a urgencias por trastorno del lenguaje y temblor, acompañados de cefalea, trastorno del comportamiento, disfunción autonómica, crisis focal motora derecha y letargo. El paciente había sido vacunado siete semanas antes con la primera dosis de la vacuna Moderna (ARN mensajero) y, cuatro semanas después de la vacunación, presentó una infección por el SARS-CoV-2 con test de antígenos positivo. Resultados. La exploración neurológica mostró un nivel de conciencia normal y una afasia mixta de predominio motor (campimetría, pares craneales, reflejos y sensibilidad normales). El test de reacción en cadena de la polimerasa para la COVID-19 fue negativo. En el líquido cefalorraquídeo se apreció una linfocitosis y proteínas elevadas. Los cultivos para hongos y bacterias fueron negativos. Los anticuerpos onconeuronales fueron normales. La resonancia magnética cerebral mostró en la secuencia de difusión una restricción con afectación cortical y morfología giral en el hemisferio cerebral izquierdo, y distribución parcheada con afectación de lóbulo frontal y temporal izquierdos. Una tomografía axial computarizada de tórax-abdomen-pelvis fue normal, al igual que las ecografías pélvica y escrotal. Al paciente se le trató con plasmaféresis y corticoides, con buena evolución clínica y resolución casi completa de las anomalías en la neuroimagen. Conclusión. Se trata de un paciente con narcolepsia de tipo 1 con criterios de encefalitis autoinmune de comienzo subagudo. La infección por el SARS-CoV-2 o la vacunación, o ambas, constituyen un riesgo para desarrollar una o más enfermedades autoinmunes con la edad ­como sucede en este caso­, lo que permite comprender la implicación de procesos inmunomediados en la fisiopatología de estas enfermedades.

Paraneoplastic encephalitis.

The first reports of encephalitis associated with cancer date to the 1960s and were characterized by clinical and pathologic involvement of limbic areas. This specific association was called limbic encephalitis (LE). The subsequent discovery of several "onconeural" antibodies (Abs), i.e., Abs targeting an antigen shared by neurons and tumor cells, supported the hypothesis of an autoimmune paraneoplastic etiology of LE and other forms of rapidly progressive encephalopathy. Over the past 20 years, similar clinical pictures with different clinical courses have been described in association with novel Abs-binding neuronal membrane proteins and proved to be pathogenic. The most well-known encephalitis in this group was described in 2007 as an association of a complex neuro-psychiatric syndrome, N-methyl-d-aspartate (NMDA) receptor-Abs, and ovarian teratoma in young women. Later on, nonparaneoplastic cases of NMDA receptor encephalitis were also described. Since then, the historical concept of LE and Ab associated encephalitis has changed. Some of these occur in fact more commonly in the absence of a malignancy (e.g., anti-LG1 Abs). Lastly, seronegative cases were also described. The term paraneoplastic encephalitis nowadays encompasses different syndromes that may be triggered by occult tumors.

General features, pathogenesis, and laboratory diagnostics of autoimmune encephalitis.

Autoimmune encephalitis (AE) is a group of inflammatory conditions that can associate with the presence of antibodies directed to neuronal intracellular, or cell surface antigens. These disorders are increasingly recognized as an important differential diagnosis of infectious encephalitis and of other common neuropsychiatric conditions. Autoantibody diagnostics plays a pivotal role for accurate diagnosis of AE, which is of utmost importance for the prompt recognition and early treatment. Several AE subgroups can be identified, either according to the prominent clinical phenotype, presence of a concomitant tumor, or type of neuronal autoantibody, and recent diagnostic criteria have provided important insights into AE classification. Antibodies to neuronal intracellular antigens typically associate with paraneoplastic neurological syndromes and poor prognosis, whereas antibodies to synaptic/neuronal cell surface antigens characterize many AE subtypes that associate with tumors less frequently, and that are often immunotherapy-responsive. In addition to the general features of AE, we review current knowledge on the pathogenic mechanisms underlying these disorders, focusing mainly on the potential role of neuronal antibodies in the most frequent conditions, and highlight current theories and controversies. Then, we dissect the crucial aspects of the laboratory diagnostics of neuronal antibodies, which represents an actual challenge for both pathologists and neurologists. Indeed, this diagnostics entails technical difficulties, along with particularly interesting novel features and pitfalls. The novelties especially apply to the wide range of assays used, including specific tissue-based and cell-based assays. These assays can be developed in-house, usually in specialized laboratories, or are commercially available. They are widely used in clinical immunology and in clinical chemistry laboratories, with relevant differences in analytic performance. Indeed, several data indicate that in-house assays could perform better than commercial kits, notwithstanding that the former are based on non-standardized protocols. Moreover, they need expertise and laboratory facilities usually unavailable in clinical chemistry laboratories. Together with the data of the literature, we critically evaluate the analytical performance of the in-house vs commercial kit-based approach. Finally, we propose an algorithm aimed at integrating the present strategies of the laboratory diagnostics in AE for the best clinical management of patients with these disorders.

Case Report: Autoimmune encephalitis and other neurological syndromes with rare neuronal surface antibody in children after hematopoietic stem cell transplantation.

Introduction: Neuronal surface antibody syndromes (NSAS) encompass a growing set of autoimmune neurological disorders, with their predominant clinical presentation being autoimmune encephalitis (AE). The most extensively documented form within NSAS is anti-N-methyl-D-aspartate receptor (NMDAR) autoimmunity. In contrast, other NSAS, such as anti-metabotropic glutamate receptor-5 (mGluR5) autoimmunity, are less common and less comprehensively characterized, particularly in pediatric cases. Case description: In this instance, we present the case of a 7-year-old girl who exhibited abnormal behaviors following hematopoietic stem cell transplantation (HSCT). She received a diagnosis of anti-mGluR5 AE, and her Electroencephalogram (EEG) displayed an increased number of generalized slow waves during wakefulness. Treatment involved intravenous administration of gamma globulin and methylprednisolone, followed by oral prednisone tablets. Levetiracetam was introduced as an antiepileptic therapy during the pulse steroid therapy. Notably, the abnormal behaviors exhibited significant improvement after treatment. Conclusions: To the best of our knowledge, this is the first report of rare pediatric NSAS involving anti-mGluR5 AE following HSCT. Enhancing our understanding and characterization of this condition may facilitate its recognition and treatment in children. Serum antibody testing could enable early identification and treatment of anti-mGluR5 AE.

Encefalitis aguda con síndrome cerebeloso secundario a neuroborreliosis / Cerebellar syndrome associated to Lyme neuroborreliosis: case report

La enfermedad de Lyme es la infección transmitida por garrapatas más común en Norteamérica y Europa. Sin embargo, en América Latina se han reportado pocos datos. Borrelia burgdorferi es capaz de invadir el sistema nervioso central causando la neuroborreliosis de Lyme. Se comunica el caso de una mujer joven con encefalitis y síndrome cerebeloso, una presentación poco frecuente, que se manifestó con cefalea, marcha atáxica, nistagmo y ptosis palpebral. Se realizó el diagnóstico con serología positiva por Western blot para Borrelia burgdorferi en suero. Recibió tratamiento con mejoría clínica. El diagnóstico de neuroborreliosis es difícil, ya que no existen hallazgos neurológicos o de imagen específicos. Se recomienda tener un mayor nivel de vigilancia epidemiológica en Latinoamérica, así como los antecedentes recreativos o viajes, que deben incluirse en la historia clínica para mejorar la aproximación diagnóstica.

Lyme disease is the most common tick-borne disease in North America and Europe. However, in Latin America, few data have been reported. Borrelia burgdorferi is capable of invading the central nervous system causing Lyme neuroborreliosis. This is a case report of a female with encephalitis and cerebellar syndrome, a rare manifestation, presented with generalized headache ataxic gait, nystagmus and palpebral ptosis. Serologic diagnosis was made for Borrelia burgdorferi and treatment was initiated with clinical improvement. Neuroborreliosis is a very difficult diagnosis, since there are no neurologic or imaging findings specific. It is recommended to physicians to have an enhanced level of surveillance in Latin America, as well as recreational/travel history of the patient, which should be included in the clinical record to improve the diagnostic approach.

[Autoimmune encephalitis and paraneoplastic neurological syndromes presenting atypical parkinsonism: a scoping review].

Recent studies have demonstrated that atypical parkinsonism can be presented in autoimmune encephalitis and paraneoplastic neurological syndromes. However, it is unclear which anti-neural antibodies are involved and when these diseases should be suspected. To address these clinical questions, we conducted a scoping review and analyzed 38 articles. The literature shows that many anti-neural antibodies, including unknown ones, have been reported in progressive supranuclear palsy, corticobasal syndrome, and multiple system atrophy. Moreover, the following symptoms and signs suggest the possibility of autoimmune encephalitis and paraneoplastic neurological syndromes: early onset, acute or subacute progression, the presence of a neoplasm, significant weight loss, abnormal cerebrospinal fluid findings, the absence of typical brain magnetic resonance imaging findings, and the existence of atypical physical examination signs.

Case report: Anti-IgLON5 disease and anti-LGI1 encephalitis following COVID-19.

Anti-IgLON family member 5 (IgLON5) disease is a rare autoimmune encephalitis, characterized by sleep problems, cognitive decline, gait abnormalities, and bulbar dysfunction. Anti-leucine-rich glioma-inactivated 1 (LGI1) autoimmune encephalitis is characterized by cognitive dysfunction, mental disorders, faciobrachial dystonic seizures (FBDS), and hyponatremia. Various studies report that coronavirus disease 2019 (COVID-19) have an effect on the nervous system and induce a wide range of neurological symptoms. Autoimmune encephalitis is one of the neurological complications in severe acute respiratory syndrome coronavirus 2 infection. Until now, autoimmune encephalitis with both anti-IgLON5 and anti-LGI1 receptor antibodies following COVID-19 is rarely reported. The case report described a 40-year-old man who presented with sleep behavior disorder, daytime sleepiness, paramnesia, cognitive decline, FBDS, and anxiety following COVID-19. Anti-IgLON5 and anti-LGI1 receptor antibodies were positive in serum, and anti-LGI1 receptor antibodies were positive in cerebrospinal fluid. The patient presented with typical symptoms of anti-IgLON5 disease such as sleep behavior disorder, obstructive sleep apnea, and daytime sleepiness. Moreover, he presented with FBDS, which is common in anti-LGI1 encephalitis. Therefore, the patient was diagnosed with anti-IgLON5 disease and anti-LGI1 autoimmune encephalitis. The patient turned better after high-dose steroid and mycophenolate mofetil therapy. The case serves to increase the awareness of rare autoimmune encephalitis after COVID-19.

Seronegative acute encephalitis following COVID-19 vaccines: a case series of an overlooked diagnosis with literature review.

PURPOSE: Autoimmune encephalitis is a neurological emergency of new-onset altered mental status, caused by an exaggerated immune-mediated response that targets the central nervous system. Autoimmune encephalitis has become an emerging differential diagnosis, when a classical infection cannot explain neurological symptoms. Displaying overlapping clinical presentations, ranging from the insidious onset of cognitive deficiency to more severe forms of encephalopathy with refractory seizures, autoimmune encephalitis can be challenging for clinicians. When evidence of malignancy is absent and pathogenic autoantibodies are undetected, with typical clinical and imaging features of autoimmune encephalitis, seronegative autoimmune encephalitis may be considered. Recently, vaccination-related autoimmune encephalitis and acute encephalitis after COVID-19 vaccination have attracted attention. METHODS AND RESULTS: We report a case series consisting of three patients with autoimmune encephalitis occurring shortly after COVID-19 vaccination and a current review of all previous reported autoimmune encephalitis related to COVID-19 vaccines. CONCLUSION: We emphasise on the prompt diagnosis of autoimmune encephalitis induced by Covid-19 vaccines and its timely treatment to improve the clinical outcome of this severe neurological condition. Post-licencing vaccine safety surveillance for potential adverse events is essential for vaccine safety and public confidence.

Paraneoplastic Kelch-like protein 11 antibody-associated cerebellar and limbic encephalitis caused by metastatic "burned-out" seminoma - A scar(r)y phenomenon.

INTRODUCTION: The diagnosis of paraneoplastic neurologic syndromes is challenging when the primary tumor masquerades as scar tissue (i.e. "burned-out"). METHODS: Case report. RESULTS: A 45-year-old male patient presented with progressive cerebellar symptoms and hearing loss. Initial screening for malignancy and extensive testing of paraneoplastic and autoimmune neuronal antibodies gave negative results. Repeated whole-body FDG-PET CT revealed a single paraaortic lymphadenopathy, metastasis of a regressed testicular seminoma. Anti-Kelch-like protein-11 (KLHL11) encephalitis was finally diagnosed. CONCLUSION: Our case highlights the importance of continued efforts to find an often burned-out testicular cancer in patients with a highly unique clinical presentation of KLHL11 encephalitis.

Specificities of Meningitis and Meningo-Encephalitis After Kidney Transplantation: A French Retrospective Cohort Study.

Kidney transplant recipients develop atypical infections in their epidemiology, presentation and outcome. Among these, meningitis and meningoencephalitis require urgent and adapted anti-infectious therapy, but published data is scarce in KTRs. The aim of this study was to describe their epidemiology, presentation and outcome, in order to improve their diagnostic and management. We performed a retrospective, multicentric cohort study in 15 French hospitals that included all 199 cases of M/ME in KTRs between 2007 and 2018 (0.9 case per 1,000 KTRs annually). Epidemiology was different from that in the general population: 20% were due to Cryptococcus neoformans, 13.5% to varicella-zoster virus, 5.5% to Mycobacterium tuberculosis, and 4.5% to Enterobacteria (half of which produced extended spectrum beta-lactamases), and 5% were Post Transplant Lymphoproliferative Disorders. Microorganisms causing M/ME in the general population were infrequent (2%, for Streptococcus pneumoniae) or absent (Neisseria meningitidis). M/ME caused by Enterobacteria, Staphylococci or filamentous fungi were associated with high and early mortality (50%-70% at 1 year). Graft survival was not associated with the etiology of M/ME, nor was impacted by immunosuppression reduction. Based on these results, we suggest international studies to adapt guidelines in order to improve the diagnosis and the probabilistic treatment of M/ME in SOTRs.

Clinical Manifestations of Monkeypox.

Monkeypox is a global health issue caused by the monkeypox virus. It can spread from person to person through respiratory secretions, direct exposure to dermatological lesions of infected patients, or exposure to contaminated objects. It is more common in homosexual men, and most patients are asymptomatic. The gold standard for diagnosis is a real-time polymerase chain reaction. In the absence of testing facilities, clinicians rely upon detailed history to exclude other causes of fever with rashes. Initially, there is a prodrome phase of a few days, which is followed by the appearance of rashes. The dermatological manifestations are in the form of an exanthematous rash, which transforms through a macular, papular, and vesicular phase and disappears after crusting in approximately 3 weeks. There can be associated lymphadenopathy in these patients. Respiratory manifestations include nasal congestion and shortness of breath that may result in secondary bacterial infections. Additionally, patients can have neurological involvement in the form of encephalitis. Furthermore, ocular involvement can occur in the form of conjunctivitis, keratitis, and corneal ulceration. Other symptoms can include diarrhea, vomiting, myalgia, and backache. Since most patients do not require hospitalization, the approach to treatment is mainly vigilant monitoring, antiviral therapy, and management of associated complications.

Acute Corticosteroid Responsive Meningoencephalitis with Cerebral Vasculitis after COVID-19 Infection in a Thirteen-Year-Old.

INTRODUCTION: Various neurologic manifestations have already been described in children during or after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. The central nervous system disorders reported in children are mainly encephalopathies during multisystem inflammatory syndrome. We present here an acute meningoencephalitis with cerebral vasculitis associated to a coronavirus disease 2019 (COVID-19) infection in a 13-year-old girl with a 1-year clinical, electroencephalogram (EEG), and magnetic resonance imaging (MRI) follow-up. CASE REPORT: A 13-year-old girl presented acute symptoms of consciousness impairment, frontal headache, hyperthermia, and aphasia, with moderate lymphopenia (900/mm3), elevated C-reactive protein (17 mg/L), cerebrospinal fluid (CSF) pleocytosis (15 cells/mm3), slow background with frontal focalization on EEG, a left frontal ischemic lesion, leptomeningeal enhancement, and bilateral limbic fluid-attenuated inversion recovery hyperintensity on cerebral MRI. Reverse transcription-polymerase chain reaction for SARS-CoV-2 was positive in nasopharyngeal swab and COVID serology was positive for immunoglobulin (Ig) M and G, whereas extensive autoimmune antibody investigation was negative except for a positive low titer of anti-myelin oligodendrocyte glycoprotein in CSF and blood. The diagnosis of probable encephalitis associated to cerebral vasculitis after COVID infection was suggested and steroids pulse were started. She recovered within a few days. Six months later, she had moderate clinical sequels including persistent intermittent headaches, an isolated spatial deficit, and focal spikes on the EEG without argument for epilepsia. CONCLUSION: A teenager without previous medical history presented with acute encephalitis with leptomeningitis and vasculitis after a recent COVID-19 infection. Steroids pulse therapy allowed clinical improvement. Cerebral MRI and EEG helped diagnosis, follow-up of the encephalitis, and evolution after treatment.

Case of clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) due to Legionella pneumonia.

Clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) is a clinicoradiologic syndrome diagnosed by temporary hyperintense lesion in the area, including the splenium of the corpus callosum, on diffusion-weighted imaging and neuropsychiatric symptoms that recover without sequelae. MERS is rare in adults, especially elderly people. We herein report a man in his 60s diagnosed with MERS caused by Legionella pneumonia. He completely recovered with only the administration of levofloxacin and azithromycin despite the risk factors of an advanced age, medical history of untreated hypertension, bilateral spontaneous pneumothoraxes, smoking and drinking habits and pulmonary emphysema. To our knowledge, this is the oldest case of MERS due to Legionella pneumonia and extremely old among total MERS cases. Our research revealed that Legionella species are the most common pathogens of adult-onset MERS, while viruses are the main causative factors in children. This case helps clarify the features of MERS in high-risk adults.

Autoimmune encephalitis after BBIBP-CorV (Sinopharm) COVID-19 vaccination: a case report.

BACKGROUND: Vaccination is an important public health strategy; however, many neurological adverse effects are associated with COVID-19 vaccination, being encephalitis a rare manifestation. CASE PRESENTATION: We present the case of a 33-year-old woman who received the first dose of the BBIBP-CorV vaccine against COVID-19 on April 4 and the second dose on April 28, 2021. Three days after receiving the second dose, she experienced a subacute episode of headache, fever, insomnia, and transient episodes of environment disconnection. We obtained negative results for infectious, systemic, and oncological causes. Brain magnetic resonance imaging showed lesions in the bilateral caudate nucleus and nonspecific demyelinating lesions at the supratentorial and infratentorial compartments. The results of the neuronal autoantibodies panel were negative. She had an adequate response to immunoglobulin and methylprednisolone; however, she experienced an early clinical relapse and received a new cycle of immunosuppressive treatment followed by a satisfactory clinical evolution. CONCLUSIONS: We report the first case of severe encephalitis associated with BBIBP-CorV (Sinopharm) vaccination in Latin America. The patient had atypical imaging patterns, with early clinical relapse and a favorable response to corticosteroid therapy.

Progress in pathogenesis and therapy of Rasmussen's encephalitis.

Rasmussen's encephalitis (RE) is a rare condition of unknown etiology that causes a severe chronically neurological disorder with mostly affecting children. The main clinical feature of RE includes frequent seizures with drug-resistant, unilateral hemispheric atrophy, and progressive neurological deficits. In this review, we summarized five pathogenesis on the basis of the current research including virus infection, antibody-mediated degeneration, cell-mediated immunity, microglia-induced degeneration, and genetic mutations. So far, no exact virus in RE brain tissue or definite antigen in humoral immune system was confirmed as the determined etiology. The importance of cytotoxic CD8+ T lymphocytes and activated microglial and the role of their immune mechanism in RE development are gradually emerging with the deep study. Genetic researches support the notion that the pathogenesis of RE is probably associated with single nucleotide polymorphisms on immune-related genes, which is driven by affecting inherent antiretroviral innate immunity. Recent advances in treatment suggest immunotherapy could partially slows down the progression of RE according to the histopathology and clinical presentation, which aimed at the initial damage to the brain by T cells and microglia in the early stage. However, the cerebral hemispherectomy is an effective means to controlling the intractable seizure, which is accompanied by neurological complications inevitably. So, the optimal timing for surgical intervention is still a challenge for RE patient. On the contrary, exploration on other aspects of pathogenesis such as dysfunction of adenosine system may offer a new therapeutic option for the treatment of RE in future.

Case Report: Paroxysmal hyperhidrosis as an initial symptom in a patient with anti-LGI1 encephalitis.

Anti-leucine-rich glioma-inactivated 1 (LGI1) encephalitis is the second most common cause of autoimmune encephalitis and is characterized by cognitive impairment, psychiatric disorders, and faciobrachial dystonic seizures. In recent decades, literature reports have expanded the phenotypic spectrum associated with the LGI1 autoantibody. The present report describes the case of a 58-year-old man who presented with repetitive unilateral hyperhidrosis of the body and arm as an initial symptom and gradually developed psychiatric symptoms, involuntary movements of the face and arms, and progressive cognitive decline. Anti-LGI1 antibodies were positive in both the serum and cerebrospinal fluid at approximately 2 months after symptom onset, and the patient was, therefore, diagnosed with anti-LGI1 encephalitis. His symptoms, namely hyperhidrosis and involuntary movements, were not relieved by antiepileptic drug treatment, but responded favorably to high-dose steroid therapy and intravenous immunoglobulin. We interpreted the repetitive unilateral hyperhidrosis as possible epilepsy. Based on this case, unilateral hyperhidrosis of the body and arm as a rare neurological presentation can be added to the phenotypic spectrum of anti-LGI1 encephalitis, and early recognition of this manifestation might support timely diagnosis and treatment.

GABA-A Receptor Encephalitis After Autologous Hematopoietic Stem Cell Transplant forMultiple Myeloma: Three Cases and Literature Review.

BACKGROUND AND OBJECTIVES: The relationship between autologous hematopoietic stem cell transplant (aHSCT) for multiple myeloma (MM) and anti-GABAA receptor (GABAAR) encephalitis is unknown. We aimed to describe the clinical features, diagnostic process, and outcome of 3 cases of anti-GABAAR encephalitis in patients with a history of prior aHSCT for MM. METHODS: A case series of 3 patients. Anti-GABAAR antibody was tested at the University of Pennsylvania Laboratory. RESULTS: The patients were all male, aged 52 (case 1), 61 (case 2), and 62 (case 3) years at encephalitis symptom onset. The duration between completion of aHSCT and the onset of encephalitis was 43, 18, and 9 months, respectively. All 3 patients presented with new seizures and altered cognitive function. Other symptoms included headache and visual obscurations in cases 1 and 2 and intractable vertigo and mania in case 3. Brain MRI demonstrated nonenhancing multifocal T2-weighted/fluid-attenuated inversion recovery cortical and subcortical hyperintensities in all 3 patients. Cases 2 and 3 underwent brain biopsy before initiating immunomodulatory therapy, which demonstrated nonspecific encephalitis with astrogliosis in the white matter; these 2 patients were started on immunotherapy for the treatment of anti-GABAAR encephalitis after 22 days and 3 months, respectively, from the first presentation. Case 1 was started on empiric immunotherapy within 8 days of presentation without requiring brain biopsy, given characteristic MRI imaging. CSF analysis demonstrated the presence of anti-GABAAR antibodies in all 3 cases. Cases 1 and 3 also tested positive for anti-GABAAR antibodies in the serum (serum test was not performed in case 2). Cases 1 and 2 recovered to work full-time within 1 year. Case 3 reported occasional myoclonic-like movement. DISCUSSION: We highlight the importance of considering anti-GABAAR encephalitis in patients with seizures, multifocal nonenhancing brain lesions, and a history of aHSCT for MM. Awareness in recovered post-aHSCT patients with MM may be crucial because prompt recognition can avoid brain biopsy and delays in treatment. The rapid initiation of immunotherapy while awaiting autoantibody results will likely improve functional outcomes.