RESUMO

Saint Louis encephalitis virus (SLEV) infection is an arbovirosis associated with a broad spectrum of neurological complications. We present a case of a 55-year-old man hailing from Manaus, a city situated in the heart of the Amazon Rainforest, who exhibited symptoms of vertigo, tremors, urinary and fecal retention, compromised gait, and encephalopathy 3 weeks following SLEV infection. Neuroaxis MRI revealed diffuse, asymmetric, and poorly defined margins hyperintense lesions with peripheral and ring enhancement in subcortical white matter, as well as severe spinal cord involvement. Serology for SLEV was positive both on serum and cerebrospinal fluid. To the best of our knowledge, the present report is the first to show brain lesions along with myelitis as a post-infectious complication of SLEV infection.

Assuntos

RESUMO

Introducción: La enfermedad asociada a anticuerpos contra la glicoproteína de mielina del oligodendrocito (MOGAD, por sus siglas en inglés) es una entidad clínica recientemente identificada. La frecuencia de presentación del MOGAD es desconocida, pero se considera baja con respecto a otras enfermedades inflamatorias desmielinizantes. Materiales y métodos: Revisión narrativa de la literatura. Resultados: Las manifestaciones clínicas de esta condición son heterogéneas e incluyen neuritis óptica, mielitis, desmielinización multifocal del sistema nervioso central y encefalitis cortical. Se han descrito algunos hallazgos radiológicos que aumentan la sospecha diagnóstica, como el realce perineural del nervio óptico, el signo de la H en el cordón espinal y la resolución de lesiones T2 con el tiempo. El diagnóstico se basa en la detección de inmunoglobulinas G específicas contra MOG, en el contexto clínico adecuado. El tratamiento consiste en manejo de los ataques agudos con dosis altas de corticoides y en algunos casos se deberá considerar la inmunosupresión crónica, considerar la inmunosupresión crónica en pacientes con recurrencia o con discapacidad severa residual tras el primer evento. Conclusiones: En esta revisión narrativa se resumen los aspectos clave con respecto a la fisiopatología, las manifestaciones, el diagnóstico y el tratamiento de la MOGAD.

Introduction: The disease associated with antibodies against the myelin oligodendrocyte glycoprotein (MOGAD) is a recently identified clinical entity, with unknown frequency, but is considered low compared to other demyelinating inflammatory diseases. Materials And Methods: Narrative review. Results: The clinical manifestations are heterogeneous, ranging from optic neuritis or myelitis to multi-focal CNS demyelination or cortical encephalitis. There have been described characteristic MRI features that increase the diagnostic suspicion, such as perineural optic nerve enhancement, spinal cord H-sign or T2-lesion resolution over time. The diagnosis is based on the detection of specific G- immunoglobulins against MOG, in the suggestive clinical context. Acute treatment is based on high dose steroids and maintenance treatment is generally reserved for relapsing cases or patients with severe residual disability after the first attack. Conclusions: In this narrative review, fundamental aspects of pathophysiology, clinical and radiological manifestations, diagnosis and treatment of MOGAD are discussed.

Assuntos

RESUMO

Background: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an inflammatory disorder of the CNS with a variety of clinical manifestations, including cerebral edema. Case Summary: A 7-year-old boy presented with headaches, nausea, and somnolence. He was found to have cerebral edema that progressed to brainstem herniation. Invasive multimodality neuromonitoring was initiated to guide management of intracranial hypertension and cerebral hypoxia while he received empiric therapies for neuroinflammation. Workup revealed serum myelin oligodendrocyte glycoprotein antibodies. He survived with a favorable neurologic outcome. Conclusion: We describe a child who presented with cerebral edema and was ultimately diagnosed with MOGAD. Much of his management was guided using data from invasive multimodality neuromonitoring. Invasive multimodality neuromonitoring may have utility in managing life-threatening cerebral edema due to neuroinflammation.

RESUMO

Abstract Background Anti-myelin oligodendrocyte glycoprotein (anti-MOG) antibody-associated disease (MOGAD) is an immune-mediated neurological disorder with a broad spectrum of clinical presentation that is often difficult to distinguish from other demyelinating diseases, such as multiple sclerosis and neuromyelitis optica spectrum disorder. Objective To describe the clinical and paraclinical characteristics of MOGAD in a Brazilian tertiary center. Methods We retrospectively reviewed the records of adult and pediatric patients who tested positive for anti-MOG antibodies and presented with clinical and radiological diseases compatible with MOGAD. Results Forty-one patients (10 children) were included: 56% female, 58% Caucasian, mean age at onset 31 years (range 6-64), with a mean disease duration of 59.6 months (range 1-264 months). The most frequent onset presentation was optic neuritis (68%), acute disseminated encephalomyelitis (ADEM, 12%), and myelitis (10%). A monophasic disease course was observed in 49%. EDSS median was 2.1 at the last visit. Most patients (83%) were under continuous immunosuppressive treatment. Azathioprine was the first-line treatment in 59%. In all ADEM cases, conus, and root involvement was radiologically observed on MRI. Conclusion Brazilian MOGAD patients presented with a similar spectrum of previously reported MOGAD phenotypes. Conus and spinal root involvement seems to be frequently present in MOGAD-ADEM and could serve as radiologic characteristics of this clinical entity.

Resumo Antecedentes A doença associada ao anticorpo da glicoproteína da mielina de oligodendrócitos (anti-MOG; MOGAD) é uma doença neurológica imunomediada com um amplo espectro de apresentações clínicas que muitas vezes é difícil de distinguir de outras doenças desmielinizantes, como a esclerose múltipla e o distúrbio do espectro da neuromielite óptica. Objetivo Descrever as características clínicas e paraclínicas da MOGAD em um centro terciário brasileiro. Métodos Revisamos retrospectivamente os prontuários dos pacientes adultos e pediátricos que testaram positivos para anticorpos anti-MOG e apresentaram um quadro clínico e radiológico compatível com MOGAD. Resultados Quarenta e um pacientes (10 crianças) foram incluídos: 56% do sexo feminino, 58% caucasianos, idade média de início da doença foi 31 anos (intervalo de 6-64), com duração média da doença de 59,6 meses (intervalo de 1-264 meses). A apresentação inicial mais frequente foi neurite óptica (68%), seguida pela encefalomielite disseminada aguda (ADEM, 12%) e mielite (10%). Um curso monofásico da doença foi observado em 49%. EDSS foi de 2,1 na última visita. A maioria dos pacientes (83%) estava sob tratamento imunossupressor contínuo. Azatioprina foi o tratamento de primeira linha em 59%. Em todos os casos de ADEM, o envolvimento do cone medular e das raízes espinhais foi observado radiologicamente na ressonância magnética. Conclusão Os pacientes brasileiros com MOGAD apresentam um espectro clínico e radiológico semelhante aos fenótipos de MOGAD relatados anteriormente. O envolvimento do cone e das raízes espinhais parece estar frequentemente presente no MOGAD-ADEM e poderia servir como característica radiológica nesta entidade.

RESUMO

Retinal complications in patients with inflammatory optic neuritis (ON) are generally related to post-infectious neuroretinitis and are considered uncommon in autoimmune/demyelinating ON, whether isolated or caused by multiple sclerosis (MS) or neuromyelitis optica spectrum disorder (NMOSD). More recently, however, cases with retinal complications have been reported in subjects positive for myelin oligodendrocyte glycoprotein (MOG) antibodies. We report a 53-year-old woman presenting with severe bilateral ON associated with a focal area of paracentral acute middle maculopathy (PAMM) in one eye. Visual loss recovered remarkably after high-dose intravenous corticosteroid treatment and plasmapheresis, but the PAMM lesion remained visible on both optical coherence tomography and angiography as an ischaemic lesion affecting the middle layers of the retina. The report emphasises the possible occurrence of retinal vascular complications in MOG-related optic neuritis, an important addition to the diagnosis of, and possible differentiation from, MS-related or NMOSD-related ON.

RESUMO

Abstract Background There is clinical and radiological overlap among demyelinating diseases. However, their pathophysiological mechanisms are different and carry distinct prognoses and treatment demands. Objective To investigate magnetic resonance imaging (MRI) features of patients with myelin-oligodendrocyte glycoprotein associated disease (MOGAD), antibody against aquaporin-4(AQP-4)-immunoglobulin G-positive neuromyelitis optica spectrum disorder (AQP4-IgG NMOSD), and double-seronegative patients. Methods A cross-sectional retrospective study was performed to analyze the topography and morphology of central nervous system (CNS) lesions. Two neuroradiologists consensually analyzed the brain, orbit, and spinal cord images. Results In total, 68 patients were enrolled in the study (25 with AQP4-IgG-positive NMOSD, 28 with MOGAD, and 15 double-seronegative patients). There were differences in clinical presentation among the groups. The MOGAD group had less brain involvement (39.2%) than the NMOSD group (p = 0.002), mostly in the subcortical/juxtacortical, the midbrain, the middle cerebellar peduncle, and the cerebellum. Double-seronegative patients had more brain involvement (80%) with larger and tumefactive lesion morphology. In addition, double-seronegative patients showed the longest optic neuritis (p = 0.006), which was more prevalent in the intracranial optic nerve compartment. AQP4-IgG-positive NMOSD optic neuritis had a predominant optic-chiasm location, and brain lesions mainly affected hypothalamic regions and the postrema area (MOGAD versus AQP4-IgG-positive NMOSD, p= 0 .013). Furthermore, this group had more spinal cord lesions (78.3%), and bright spotty lesions were a paramount finding to differentiate it from MOGAD (p = 0.003). Conclusion The pooled analysis of lesion topography, morphology, and signal intensity provides critical information to help clinicians form a timely differential diagnosis.

Resumo Antecedentes Há sobreposição clínica e radiológica entre as doenças desmielinizantes. No entanto, seus mecanismos fisiopatológicos são diferentes e apresentam prognósticos e demandas de tratamento distintos. Objetivo Investigar as características de imagens de RM dos pacientes com doença associada à glicoproteína de oligodendrócito de mielina (MOGAD), a doenças do espectro da neuromielite óptica positivas para antiaquaporina-4 imunoglobulina G (AQP4-IgG NMOSD), e pacientes duplamente soronegativos. Métodos Estudo retrospectivo e transversal para analisar as características e frequência das lesões do sistema nervoso central (SNC). Dois neurorradiologistas avaliaram consensualmente as imagens do cérebro, das órbitas e da medula espinhal. Resultados Ao todo, foram incluídos 68 pacientes(25 com AQP4-IgG NMOSD, 28 com MOGAD e 15 duplo-soronegativos). Há diferenças na apresentação clínica entre os grupos. O grupo MOGAD demonstrou menor frequência de comprometimento do cérebro (39.2%) comparado com o AQP4-IgG NMOSD (p = 0.002), com predomínio da distribuição das lesões nas regiões subcortical/justacortical, mesencéfalo, pedúnculos cerebelares médios e cerebelo. O grupo duplo-soronegativo demonstrou maior frequência de comprometimento do cérebro (80%), com lesões de maiores dimensões e com morfologia tumefeita, além de neurite óptica com maior extensão (p = 0.006). O grupo AQP4-IgG NMOSD demonstrou neurite óptica com predomínio na região óptico-quiasmática e as lesões encefálicas acometeram predominantemente as regiões hipotalâmica e área postrema (MOGAD versus AQP4-IgG NMOSD p = 0.013). Além disso, foram observadas mais lesões na medula espinhal (78.3%) e a presença da "bright spotty lesion" foi um achado primordial para a sua diferenciação com os pacientes MOGAD (p = 0.003). Conclusão A análise pormenorizada das características das lesões por RM dos pacientes com doenças desmielinizantes imunomediadas fornece informações fundamentais que auxiliam os médicos no diagnóstico diferencial em um momento oportuno.

RESUMO

ABSTRACT Myelin oligodendrocyte glycoprotein-immunoglobulin G (IgG)-associated optic neuritis has been established as a new entity of immune-mediated optic neuropathy. Patients usually present with recurrent optic neuritis, often bilaterally with initially severe vision loss and optic disc edema. However, in contrast to aquaporin 4-IgG-seropositive neuromyelitis optica spectrum disorder, visual recovery tends to be more favorable, with good response to steroid treatment. Another important differential diagnosis of myelin oligodendrocyte glycoprotein-IgG--associated optic neuritis is multiple sclerosis. Close monitoring for signs of relapse and long-term immunosuppression may be considered to maintain optimal visual function. The diagnosis can be made on the basis of the presence of a specific, usually serological, antibody against myelin oligodendrocyte glycoprotein (IgG; cell-based assay), and a demyelinating event (optic neuritis, myelitis, brainstem syndrome, or cortical lesions with seizures). The clinical spectrum of this newly recognized inflammatory demyelinating disease is expanding rapidly. We briefly review the epidemiological characteristics, clinical manifestations, diagnostic considerations, and treatment options of myelin oligodendrocyte glycoprotein-IgG-associated optic neuritis.

RESUMO A neurite óptica associada à glicoproteína de oligodendrócito de mielina-IgG foi estabelecida como uma nova entidade de neuropatia óptica imunomediada. Tipicamente os pacientes apresentam neurite óptica recorrente, muitas vezes bilateral, com perda de visão frequentemente severa e alta prevalência de edema do disco óptico na fase aguda. No entanto, em contraste com neuromyelitis optica spectrum disorder associada com presença de anticorpo contra aquaporina 4, a recuperação visual tende a ser mais favorável e responde bem ao tratamento com corticoide em altas doses. A esclerose múltipla representa outro importante diagnóstico diferencial de glicoproteína de oligodendrócito de mielina-IgG. O diagnóstico pode ser feito com base na presença de um anticorpo específico, geralmente sorológico contra glicoproteína de oligodendrócito de mielina (IgG, ensaio baseado em células), e presença de evento desmielinizante (neurite óptica, mielite, síndrome do tronco cerebral, lesões corticais com convulsões). O espectro clínico desta doença desmielinizante inflamatória recém-reconhecida está se expandindo rapidamente. Faremos uma breve revisão das características epidemiológicas, manifestações clínicas, considerações diagnósticas e opções de tratamento da neurite óptica associada à glicoproteína de oligodendrócito de mielina-IgG.

Assuntos

RESUMO

BACKGROUND: Anti-Myelin Oligodendrocyte Glycoprotein (MOG) Antibody Associated Disease (MOGAD) is an emerging disorder recognized as a clinical entity distinct from Multiple Sclerosis and Aquaporin-4-positive Neuromyelitis Optica Spectrum Disorders (NMOSD-AQP4+), and its phenotypic spectrum continues to expand. Most information about its clinical course has emerged from retrospective studies, and treatment response both in acute and chronic-relapsing disease is still limited. We aimed to describe the clinical and paraclinical characteristics of monophasic and relapsing, paediatric and adult patients with MOGAD under regular clinical care in Chile, highlighting some challenging cases that are far from being considered benign. METHODS: Observational, retrospective, and prospective longitudinal multicentre study including patients with positive serum MOG-IgG assessed by cell-based assay. RESULTS: We include 35 patients, 71% women, median age at onset 30 years (range 1-68), 23% had paediatric onset, with a median disease-duration 24 months (range 12-348). In the whole cohort, the most frequent symptoms at onset were isolated optic neuritis (ON) (34%) and myelitis (22%). Encephalitis with seizures or encephalomyelitis was the most common presentation in paediatric-onset patients 75% (n = 6), compared to 11% (n = 3) of the adult-onset patients (p < 0.001). A relapsing course was observed in 34%, these patients were younger (25 vs. 34 years, p = 0.004) and with a longer disease duration (64 vs. 6 months, p = 0.004) compared to monophasic patients. Two patients developed encephalitis with seizures/status epilepticus, with concomitant positive CSF anti-NMDAR-IgG. Chronic immunotherapy was ever prescribed in 77%, the most frequent was rituximab (35%). Relapses under chronic immunotherapy occurred in 5/27 patients (18.5%), two of them under rituximab, one paediatric patient who started combined therapy with monthly IVIG and one adult patient that switched to satralizumab plus mycophenolate. The median EDSS at the last follow-up was 1.5 (range 0-6.0). CONCLUSION: In Chile, patients with MOGAD exhibit a wide spectrum of clinical presentations at disease onset and during relapses. Close monitoring is needed, particularly in younger patients with short follow-up periods.

Assuntos

RESUMO

BACKGROUND: Several MRI findings of optic neuritis (ON) have been described and correlated with specific underlying etiologies. Specifically, optic nerve enhancement is considered an accurate biomarker of acute ON. OBJECTIVE: To identify differences in MRI patterns of optic nerve enhancement in certain demyelinating etiologies presenting with acute ON. METHODS: Retrospective analysis of enhancement patterns on fat-suppressed T1-weighted images from patients presenting clinical and radiological acute ON, treated at our institution between January 2014 and June 2022. Location and extension of enhancing optic nerve segments, as well as presence of perineural enhancement were evaluated in three predetermined demyelinating conditions. Fisher's exact test and chi2 were calculated. RESULTS: Fifty-six subjects met eligibility criteria. Mean age was 31 years (range 6-79) and 70% were females. Thirty-four (61%) patients were diagnosed with multiple sclerosis (MS), 8 (14%) with neuromyelitis optica (NMO), and 14 (25%) with anti-myelin oligodendrocyte glycoprotein disease (MOGAD). Bilateral involvement was more frequent in MOGAD, compared to MS and NMO (43 vs 3% and 12.5% respectively, p = 0.002). MS patients showed shorter optic nerve involvement, whereas MOGAD showed more extensive lesions (p = 0.006). Site of involvement was intraorbital in 63% MS, 89% NMO, 90% MOGAD (p = 0.051) and canalicular in 43% MS, 33% NMO and 75% MOGAD (p = 0.039). Intracranial or chiasmatic involvement and presence of perineural enhancement were not statistically different between entities. CONCLUSION: In the setting of acute ON, patients presenting MOGAD were more likely to show bilateral, longitudinally extended and anterior (intraorbital and canalicular) optic nerve involvement compared to patients with MS or NMO.

Assuntos

RESUMO

Abstract Neuromyelitis optica spectrum disorder (NMOSD) is a rare and severe inflammatory disorder of the central nervous system (CNS). It is strongly associated with anti-aquaporin 4 antibodies (AQP4-IgG), and it mainly affects young women from non-white ethnicities. However, ~ 5 to 10% of all cases have onset during childhood. Children and adolescents share the same clinical, radiologic, and laboratory presentation as adults. Thus, the same NMOSD diagnostic criteria are also applied to pediatric-onset patients, but data on NMOSD in this population is still scarce. In seronegative pediatric patients, there is a high frequency of the antibody against myelin oligodendrocyte glycoprotein (MOG-IgG) indicating another disease group, but the clinical distinction between these two diseases may be challenging. Three drugs (eculizumab, satralizumab, and inebilizumab) have been recently approved for the treatment of adult patients with AQP4-IgG-positive NMOSD. Only satralizumab has recruited adolescents in one of the two pivotal clinical trials. Additional clinical trials in pediatric NMOSD are urgently required to evaluate the safety and efficacy of these drugs in this population.

Resumo O espectro da neuromielite óptica (ENMO) é uma rara e grave doença inflamatória do sistema nervoso central (SNC), fortemente associada ao anticorpo anti-aquaporina 4 (AQP4-IgG) e que afeta preferencialmente mulheres jovens de etnias não-caucasianas. No entanto, aproximadamente de 5 a 10% de todos os casos se iniciam na infância. Crianças e adolescentes compartilham as mesmas características clínicas, radiológicas e laboratoriais dos adultos. Além disso, o mesmo critério diagnóstico de ENMO é aplicado para pacientes com início na infância. No entanto, dados da população pediátrica são escassos. Em pacientes pediátricos soronegativos, existe uma alta frequência de positividade ao anticorpo contra a glicoproteína na mielina do oligodendrócito (MOG-IgG), indicando outra patologia; porém, a distinção clínica entre as duas doenças é desafiadora. Três medicações (eculizumabe, inebilizumabe e satralizumabe) foram recentemente aprovadas para pacientes adultos com AQP4-IgG. Apenas um dos ensaios pivotais do satralizumabe recrutou adolescentes. Novos ensaios clínicos em pacientes pediátricos com ENMO são necessários para avaliar a segurança e eficácia destas drogas nesta população.

RESUMO

ABSTRACT Background: Acquired demyelinating disorders lead to overlapping visual, pyramidal, sensory, autonomic, and cerebellar deficits and may lead to severe disability. Early diagnosis and start of treatment are fundamental towards preventing further attacks and halting disability. Objective: In this paper we provide an updated overview of the differential diagnoses of acquired demyelinating disorders. Methods: We performed a critical targeted review of the diagnoses of the most prevalent demyelinating disorders: multiple sclerosis (MS), neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein antibody disease (MOGAD). Results: We discuss the workup, diagnostic criteria and new biomarkers currently being used for the diagnosis of these disease entities taking into account the particularities of the Brazilian population and healthcare system. Conclusion: A comprehensive analysis of medical history, physical examination, biomedical and imaging data should be performed to obtain differential diagnosis. Diagnostic criteria should be mindfully employed considering ethnic and environmental particularities of each patient.

RESUMO Antecedentes: Doenças desmielinizantes adquiridas levam a déficits visuais, piramidais, sensitivos, autonômicos e cerebelares que se sobrepõem e podem conduzir a grave incapacidade. O diagnóstico e o início de tratamento precoces são fundamentais para a prevenção de surtos e ocorrência de incapacidade. Objetivo: Neste artigo, apresentamos uma visão geral atualizada sobre o diagnóstico diferencial de doenças desmielinizantes adquiridas. Métodos: Realizamos uma revisão crítica sobre o diagnóstico das doenças desmielinizantes mais prevalentes: esclerose múltipla (EM), doença do espectro neuromielite óptica (NMOSD) e doença associada ao anticorpo contra a glicoproteína da mielina do oligodendrócito (MOGAD). Resultados: Discutimos a investigação, os critérios diagnósticos e os novos biomarcadores atualmente empregados para o diagnóstico dessas doenças, levando em conta as particularidades da população e sistema de saúde brasileiros. Conclusão: Uma análise minuciosa do histórico médico, exame neurológico e exames biomédicos e de imagem deve ser realizada para se fazer um diagnóstico diferencial de doença desmielinizante. Critérios diagnósticos devem ser empregados cautelosamente considerando-se particularidades étnicas e ambientais de cada paciente.

RESUMO

BACKGROUND AND PURPOSE: Optic neuritis (ON) is often the initial symptom of neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein-associated disease (MOGAD). We aimed to compare the frequency and pattern of chiasmatic lesions in MOGAD-related ON (MOGAD-ON) and NMOSD-related ON (NMOSD-ON) using conventional brain imaging (magnetic resonance imaging [MRI]) in Latin America (LATAM). METHODS: We reviewed the medical records and brain MRI (≤30 days from ON onset) of patients with a first event of MOGAD-ON and NMOSD-ON. Patients from Argentina (n = 72), Chile (n = 21), Ecuador (n = 31), Brazil (n = 30), Venezuela (n = 10) and Mexico (n = 82) were included. Antibody status was tested using a cell-based assay. Demographic, clinical, imaging and prognostic (as measured by the Visual Functional System Score [VFSS] of the Expanded Disability Status Scale) data were compared. RESULTS: A total of 246 patients (208 NMOSD and 38 MOGAD) were included. No differences were found in gender and ethnicity between the groups. We observed chiasmatic lesions in 66/208 (31.7%) NMOSD-ON and in 5/38 (13.1%) MOGAD-ON patients (p = 0.01). Of these patients with chiasmatic lesions, 54/66 (81.8%) and 4/5 had associated longitudinally extensive optic nerve lesions, 45/66 (68%) and 4/5 had bilateral lesions, and 31/66 (47%) and 4/5 showed gadolinium-enhancing chiasmatic lesions, respectively. A positive correlation was observed between VFSS and presence of bilateral (r = 0,28, p < 0.0001), chiasmatic (r = 0.27, p = 0.0001) and longitudinally extensive lesions (r = 0,25, p = 0.0009) in the NMOSD-ON group, but no correlations were observed in the MOGAD-ON group. CONCLUSIONS: Chiasmatic lesions were significantly more common in NMOSD than in MOGAD during an ON attack in this LATAM cohort. Further studies are needed to assess the generalizability of these results.

Assuntos

RESUMO

Human antibodies against Myelin Oligodendrocyte Glycoprotein (MOG) from immunoglobulin-G subclasses (MOG-IgG) have been recently associated with a new subgroup of neurological autoimmune diseases with distinct clinical characteristics from multiple sclerosis and neuromyelitis optica spectrum disorders. The use of MOG-IgG as a biomarker is an essential tool to assist in the diagnosis and clinical prognosis. The cell-based assay (CBA) is a methodology that expresses high levels of natively folded human MOG protein in the cell membrane being the methodology most used for clinical MOG-IgG diagnosis. However, there is still no consensus about the best approach to perform CBA to improve the results. The CBA using flow cytometry (CBA-FC) is an automated technique with objective quantification, reducing the subject of human bias that occurred at CBA using immunofluorescence (CBA-IF). In this study, we compared the performance of CBA-IF and CBA-FC as an acquisition tool analysis. The sera of 104 patients diagnosed with inflammatory Central Nervous System diseases were tested in both CBA-IF and CBA-FC. We used the dilution of 1:128 for CBA-IF and three different dilutions (1:20, 1:100, and 1:640) for CBA-FC. The CBA-FC and CBA-IF results had 88.5% agreement between assays and the CBA-IF titers by endpoint-dilution correlated with the CBA-FC titers. The highest serum dilution resulted in an increased CBA-FC specificity, but there was a reduction in the CBA-FC sensitivity. Our study showed that CBA-FC can be used in clinical practice as a diagnostic technique for MOG-IgG. In addition, in some specific cases, the combination of both techniques could be used as a tool to discriminate unspecific binding and overcome single assay limitations.

Assuntos

RESUMO

BACKGROUND: Myelin oligodendrocyte glycoprotein antibodies (MOG-ab) have been described in aquaporin-4-antibodies(AQP4-ab)-negative neuromyelitis optica spectrum disorder (NMOSD) patients. We aimed to evaluate the percentage of AQP4-ab-negative NMOSD patients who are positive for MOG-ab in a cohort of Argentinean patients included in RelevarEM (Clinical Trials registry number NCT03375177). METHODS: RelevarEM is a longitudinal, strictly observational multiple sclerosis (MS) and NMOSD registry in Argentina. Of 3031 consecutive patients (until March 2020), 165 patients with phenotype of suspected NMOSD, whose relevant data for the purpose of this study were available, were included. Data on demographic, clinical, paraclinical and treatment in AQP4-ab (positive, negative and unknown) and MOG-ab (positive and negative) patients were evaluated. RESULTS: A total of 165 patients (79 AQP4-Ab positive, 67 AQP4-Ab negative and 19 unknown) were included. Of these, 155 patients fulfilled the 2015 NMOSD diagnostic criteria. Of 67 AQP4-Ab-negative patients, 36 (53.7%) were tested for MOG-Ab and 10 of them (27.7%) tested positive. Serum AQP4-ab levels were tested by means of cell-based assay (CBA) in 48 (35.2%), based on tissue-based indirect immunofluorescence assays in 58 (42.6%) and enzyme-linked immunosorbent assay in 4 (2.9%). All MOG-ab were tested by CBA. Optic neuritis (90%) was the most frequent symptom at presentation and optic nerve lesions the most frequent finding (80%) in neuroimaging of MOG-ab-associated disease. Of these, six (60%) patients were under immunosuppressant treatments at latest follow-up. CONCLUSION: We observed that 27.7% (10/36) of the AQP4-ab-negative patients tested for MOG-ab were positive for this antibody, in line with results from other world regions.

Assuntos

RESUMO

Myelin oligodendrocyte glycoprotein (MOG) is a unique CNS-specific mammalian protein that is expressed on the surface of compact myelin and oligodendrocyte cell bodies. MOG is an accessible target for autoantibodies, associated with immune-mediated demyelination in the central nervous system. The identification of MOG reactive immunoglobulin G antibodies (MOG-IgG) helps to distinguish a subgroup of patients from multiple sclerosis and other CNS disorders, reducing the risk of clinical misdiagnosis. The development of the cell-based assays (CBA) improved the detection of clinically meaningful MOG-IgG binding to conformational MOG expressed in the cell membrane surface. In this review, we describe factors that impact on the results of CBA, such as MOG conformation, protein glycosylation, addition of fluorescent tags, serum dilution, secondary antibodies, and data interpretation.

Assuntos

RESUMO

Acute disseminated encephalomyelitis (ADEM) is an immune-mediated central nervous system (CNS) disorder, characterized by polyfocal symptoms, encephalopathy and typical magnetic resonance imaging (MRI) findings, that especially affects young children. Advances in understanding CNS neuroimmune disorders as well as the association of myelin oligodendrocyte glycoprotein antibody (MOG-Ab) with both monophasic and recurrent forms of ADEM have led to new insights into its definition, management and outcome. In this review, we aim to provide an update based on current epidemiologic, clinical, radiological and immunopathological aspects and clinical outcome of ADEM.

RESUMO

Diagnostic accuracy is poor in demyelinating myelopathies, and therefore a challenge for neurologists in daily practice, mainly because of the multiple underlying pathophysiologic mechanisms involved in each subtype. A systematic diagnostic approach combining data from the clinical setting and presentation with magnetic resonance imaging (MRI) lesion patterns, cerebrospinal fluid (CSF) findings, and autoantibody markers can help to better distinguish between subtypes. In this review, we describe spinal cord involvement, and summarize clinical findings, MRI and diagnostic characteristics, as well as treatment options and prognostic implications in different demyelinating disorders including: multiple sclerosis (MS), neuromyelitis optica spectrum disorder, acute disseminated encephalomyelitis, anti-myelin oligodendrocyte glycoprotein antibody-associated disease, and glial fibrillary acidic protein IgG-associated disease. Thorough understanding of individual case etiology is crucial, not only to provide valuable prognostic information on whether the disorder is likely to relapse, but also to make therapeutic decision-making easier and reduce treatment failures which may lead to new relapses and long-term disability. Identifying patients with monophasic disease who may only require acute management, symptomatic treatment, and subsequent rehabilitation, rather than immunosuppression, is also important.

RESUMO

Background Experimental autoimmune encephalomyelitis (EAE) is the most commonly used and clinically relevant murine model for human multiple sclerosis (MS), a demyelinating autoimmune disease characterized by mononuclear cell infiltration into the central nervous system (CNS). The aim of the present study was to appraise the alterations, poorly documented in the literature, which may occur at the peripheral nervous system (PNS) level. Methods To this purpose, a multiple evaluation of peripheral nerve excitability was undertaken, by means of a minimally invasive electrophysiological method, in EAE mice immunized with the myelin oligodendrocyte glycoprotein (MOG) 35-55 peptide, an experimental model for MS that reproduces, in animals, the anatomical and behavioral alterations observed in humans with MS, including CNS inflammation, demyelination of neurons, and motor abnormalities. Additionally, the myelin sheath thickness of mouse sciatic nerves was evaluated using transmission electronic microscopy. Results As expected, the mean clinical score of mice, daily determined to describe the symptoms associated to the EAE progression, increased within about 18 days after immunization for EAE mice while it remained null for all control animals. The multiple evaluation of peripheral nerve excitability, performed in vivo 2 and 4 weeks after immunization, reveals that the main modifications of EAE mice, compared to control animals, are a decrease of the maximal compound action potential (CAP) amplitude and of the stimulation intensity necessary to generate a CAP with a 50% maximum amplitude. In addition, and in contrast to control mice, at least 2 CAPs were recorded following a single stimulation in EAE animals, reflecting various populations of sensory and motor nerve fibers having different CAP conduction speeds, as expected if a demyelinating process occurred in the PNS of these animals. In contrast, single CAPs were always recorded from the sensory and motor nerve fibers of control mice having more homogeneous CAP conduction speeds. Finally, the myelin sheath thickness of sciatic nerves of EAE mice was decreased 4 weeks after immunization when compared to control animals. Conclusions In conclusion, the loss of immunological self-tolerance to MOG in EAE mice or in MS patients may not be only attributed to the restricted expression of this antigen in the immunologically privileged environment of the CNS but also of the PNS.

RESUMO

Neuromyelitis optica (NMO) is an autoimmune, inflammatory and de myelinat ing disorder of the central nervous system with a predilection for the optic nerves and spinal cord. In 2004 the association of NMO with an antibody against the water channel aquaporin 4 (anti-AQP4) was published as a different pathology from multiple sclerosis (MS). Currently the term NMO spectrum disorders (NMOSD) is proposed, because the manifestations of the disease can be more extensive, affecting in addition to the optic nerve and spinal cord, the area postrema of the dorsal medulla, brainstem, diencephalon and typical brain areas (periependymal, corpus callosum, internal capsule and subcortical white matter). NMOSD is also applied to patients who meet the NMO criteria and are negative for AQP4-IgG. Within the latter group, the presence of another antibody, anti-MOG, has been detected in 20%, with a different physiopathological mechanism, but with a similar clinic and a better prognosis. The immunosuppressive treatment in the attack, as well as the long-term treatment in the cases that are indicated, is fundamental to avoid sequelaes and recurrences. The correct diagnosis of this entity is essential since it can be aggravated with the use of drugs useful in the treatment of MS. In this publication we will review the pathophysiology, clinical and diagnostic criteria of NMOSD, and discuss the different therapeutic options.

La neuromielitis óptica (NMO) es un trastorno autoinmune, inflamatorio y desmielinizante del sistema nervioso central con predilección por los nervios ópticos y médula espinal. En el año 2004 se publicó la asociación de NMO con un anticuerpo contra el canal de agua acuaporina 4 (anti-AQP4), como una enfermedad diferente de la esclerosis múltiple (EM). Actualmente se propone el término trastornos del espectro NMO (NMOSD), debido a que las manifestaciones de la enfermedad pueden ser más extensas, afectando además del nervio óptico y médula espinal, al área postrema del bulbo raquídeo, tronco encefálico, diencéfalo y áreas cerebrales típicas (periependimarias, cuerpo calloso, cápsula interna y sustancia blanca subcortical). NMOSD se aplica también a pacientes que cumplen los criterios de NMO y son negativos para anti-AQP4. Dentro de este último grupo se ha detectado en un 20% la presencia de otro anticuerpo, anti-MOG (Glicoproteína oligodendrocítica de mielina) con un mecanismo fisiopatológico diferente pero con una clínica, en algunos casos, similar, y en general con mejor pronóstico. El tratamiento inmunosupresor en la crisis, así como el tratamiento a largo plazo en los casos que esté indicado, es fundamental para evitar secuelas y recidivas. El diagnóstico correcto de esta entidad es fundamental ya que puede ser agravado con el uso de fármacos útiles en el tratamiento de EM. En esta publicación haremos una revisión de la fisiopatología, clínica y criterios diagnósticos de NMOSD, y discutiremos las distintas opciones terapéuticas.

Assuntos

RESUMO

La neuromielitis óptica (NMO) es un trastorno autoinmune, inflamatorio y desmielinizante del sistema nervioso central con predilección por los nervios ópticos y médula espinal. En el año 2004 se publicó la asociación de NMO con un anticuerpo contra el canal de agua acuaporina 4 (anti-AQP4), como una enfermedad diferente de la esclerosis múltiple (EM). Actualmente se propone el término trastornos del espectro NMO (NMOSD), debido a que las manifestaciones de la enfermedad pueden ser más extensas, afectando además del nervio óptico y médula espinal, al área postrema del bulbo raquídeo, tronco encefálico, diencéfalo y áreas cerebrales típicas (periependimarias, cuerpo calloso, cápsula interna y sustancia blanca subcortical). NMOSD se aplica también a pacientes que cumplen los criterios de NMO y son negativos para anti-AQP4. Dentro de este último grupo se ha detectado en un 20% la presencia de otro anticuerpo, anti-MOG (Glicoproteína oligodendrocítica de mielina) con un mecanismo fisiopatológico diferente pero con una clínica, en algunos casos, similar, y en general con mejor pronóstico. El tratamiento inmunosupresor en la crisis, así como el tratamiento a largo plazo en los casos que esté indicado, es fundamental para evitar secuelas y recidivas. El diagnóstico correcto de esta entidad es fundamental ya que puede ser agravado con el uso de fármacos útiles en el tratamiento de EM. En esta publicación haremos una revisión de la fisiopatología, clínica y criterios diagnósticos de NMOSD, y discutiremos las distintas opciones terapéuticas.

Neuromyelitis optica (NMO) is an autoimmune, inflammatory and de myelinat ing disorder of the central nervous system with a predilection for the optic nerves and spinal cord. In 2004 the association of NMO with an antibody against the water channel aquaporin 4 (anti-AQP4) was published as a different pathology from multiple sclerosis (MS). Currently the term NMO spectrum disorders (NMOSD) is proposed, because the manifestations of the disease can be more extensive, affecting in addition to the optic nerve and spinal cord, the area postrema of the dorsal medulla, brainstem, diencephalon and typical brain areas (periependymal, corpus callosum, internal capsule and subcortical white matter). NMOSD is also applied to patients who meet the NMO criteria and are negative for AQP4-IgG. Within the latter group, the presence of another antibody, anti-MOG, has been detected in 20%, with a different physiopathological mechanism, but with a similar clinic and a better prognosis. The immunosuppressive treatment in the attack, as well as the long-term treatment in the cases that are indicated, is fundamental to avoid sequelaes and recurrences. The correct diagnosis of this entity is essential since it can be aggravated with the use of drugs useful in the treatment of MS. In this publication we will review the pathophysiology, clinical and diagnostic criteria of NMOSD, and discuss the different therapeutic options.

Assuntos