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

INTRODUCTION We present a narcolepsy type 1 patient that develop an autoimmune encephalitis post vaccine and/or a SARS-CoV-2 infection.CASE REPORTAt 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).RESULTSThe 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. (AU)

Clinical and neuroimaging phenotypes of autoimmune glial fibrillary acidic protein astrocytopathy: A systematic review and meta-analysis.

OBJECTIVE: This study was undertaken to provide a comprehensive review of neuroimaging characteristics and corresponding clinical phenotypes of autoimmune glial fibrillary acidic protein astrocytopathy (GFAP-A), a rare but severe neuroinflammatory disorder, to facilitate early diagnosis and appropriate treatment. METHODS: A PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis)-conforming systematic review and meta-analysis was performed on all available data from January 2016 to June 2023. Clinical and neuroimaging phenotypes were extracted for both adult and paediatric forms. RESULTS: A total of 93 studies with 681 cases (55% males; median age = 46, range = 1-103 years) were included. Of these, 13 studies with a total of 535 cases were eligible for the meta-analysis. Clinically, GFAP-A was often preceded by a viral prodromal state (45% of cases) and manifested as meningitis, encephalitis, and/or myelitis. The most common symptoms were headache, fever, and movement disturbances. Coexisting autoantibodies (45%) and neoplasms (18%) were relatively frequent. Corticosteroid treatment resulted in partial/complete remission in a majority of cases (83%). Neuroimaging often revealed T2/fluid-attenuated inversion recovery (FLAIR) hyperintensities (74%) as well as perivascular (45%) and/or leptomeningeal (30%) enhancement. Spinal cord abnormalities were also frequent (49%), most commonly manifesting as longitudinally extensive myelitis. There were 88 paediatric cases; they had less prominent neuroimaging findings with lower frequencies of both T2/FLAIR hyperintensities (38%) and contrast enhancement (19%). CONCLUSIONS: This systematic review and meta-analysis provide high-level evidence for clinical and imaging phenotypes of GFAP-A, which will benefit the identification and clinical workup of suspected cases. Differential diagnostic cues to distinguish GFAP-A from common clinical and imaging mimics are provided as well as suitable magnetic resonance imaging protocol recommendations.

Autoimmune encephalitis related to LGI1 antibodies with negative MRI study: Description of two cases / Encefalitis autoinmune relacionada con anticuerpos LGI1 con estudio de RM negativo: descripción de dos casos

Background Leucine-rich glioma inactivated 1 (LGI1) antibody-related autoimmune encephalitis is easily misdiagnosed clinically because of its complex and diverse clinical manifestations. We present two cases of LGI1 antibody-related encephalitis with negative imaging findings and perform a literature review on this disease entity. Case description The first case was that of a 60-year-old man who presented with involuntary movement of the paroxysmal right limb. The second case was that of a 66-year-old man who presented with hearing hallucinations, involuntary shaking of the right limb, and progressive cognitive impairment. Both patients in this study showed negative magnetic resonance imaging (MRI) results. Routine cerebrospinal fluid (CSF) and biochemical examinations showed no significant abnormalities, and positive LGI1 antibodies were detected in both the CSF and serum. Conclusion Based on our experience and the literature review, we recommend that LGI1 antibody-related encephalitis should be considered when faciobrachial dystonic seizures, acute and subacute-onset seizures, low serum sodium (possibly with low CSF chloride), and cognitive-psychiatric disorders are encountered, even in the absence of specific radiographic and altered CSF findings (AU)

Antecedentes La encefalitis autoinmunitaria relacionada con anticuerpos LGI1 puede ser fácilmente mal diagnosticada clínicamente debido a sus manifestaciones clínicas complejas y diversas. Presentamos dos casos de encefalitis relacionada con anticuerpos LGI1 con hallazgos de imágenes negativas y realizamos una revisión de la literatura sobre esta entidad patológica. Descripción de casos El primer caso fue el de un hombre de 60años que presentó movimientos involuntarios del miembro derecho paroxístico. El segundo caso fue el de un hombre de 66años que presentó alucinaciones auditivas, temblores involuntarios del miembro derecho y un deterioro cognitivo progresivo. Ambos pacientes en este estudio mostraron resultados negativos de imágenes por resonancia magnética (RM). Los exámenes rutinarios de líquido cefalorraquídeo (LCR) y bioquímicos no mostraron anomalías significativas, pero se detectaron anticuerpos LGI1 positivos en ambos: LCR y suero. Conclusión Basándonos en nuestra experiencia y en la revisión de la literatura, recomendamos considerar la posibilidad de encefalitis relacionada con anticuerpos LGI1 cuando aparezcan crisis distónicas faciobraquiales, convulsiones de inicio agudo o subagudo, hiponatremia (posiblemente con hipoclorhidria del LCR) y trastornos cognitivo-psiquiátricos, incluso en ausencia de hallazgos radiográficos específicos o modificaciones en el LCR (AU)

Autoimmune encephalitis related to LGI1 antibodies with negative MRI study: Description of two cases.

BACKGROUND: Leucine-rich glioma inactivated 1 (LGI1) antibody-related autoimmune encephalitis is easily misdiagnosed clinically because of its complex and diverse clinical manifestations. We present two cases of LGI1 antibody-related encephalitis with negative imaging findings and perform a literature review on this disease entity. CASE DESCRIPTION: The first case was that of a 60-year-old man who presented with involuntary movement of the paroxysmal right limb. The second case was that of a 66-year-old man who presented with hearing hallucinations, involuntary shaking of the right limb, and progressive cognitive impairment. Both patients in this study showed negative magnetic resonance imaging (MRI) results. Routine cerebrospinal fluid (CSF) and biochemical examinations showed no significant abnormalities, and positive LGI1 antibodies were detected in both the CSF and serum. CONCLUSION: Based on our experience and the literature review, we recommend that LGI1 antibody-related encephalitis should be considered when faciobrachial dystonic seizures, acute and subacute-onset seizures, low serum sodium (possibly with low CSF chloride), and cognitive-psychiatric disorders are encountered, even in the absence of specific radiographic and altered CSF findings.

Clinical characteristics of autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy in children: A case series of 16 patients.

PURPOSE: To investigate the clinical characteristics of autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy in children. METHODS: We reviewed the medical records of Children's Hospital of Chongqing Medical University from January 2020 to September 2021 and retrospectively analysed the clinical features, magnetic resonance imaging (MRI) findings, laboratory findings, treatment and outcome of children with autoimmune GFAP astrocytopathy. RESULTS: Sixteen patients were included: 6 and 10 tested positive for GFAP-IgG in cerebrospinal fluid (CSF) and both CSF and serum, respectively. The median patient age was 115 months (range: 36-180 months), and 7 patients (43.8%) were male. All patients had the clinical syndrome of encephalitis/meningoencephalitis with or without myelitis: encephalitis (8), meningoencephalitis (3), encephalomyelitis (1) and meningoencephalomyelitis (4). The most common clinical symptoms were fever (11), altered consciousness (11), headache (10) and seizure (9). Four patients developed central respiratory failure for which mechanical ventilation was needed. All patients showed hyperintense T2-weighted lesions on brain MRI in the cerebral white matter (13), brainstem (11), basal ganglia (11), thalamus (9), and cerebellum (3). Nine patients (56%) had abnormal hyperintense lesions in the bilateral basal ganglia and thalamus. Six of 12 patients who underwent gadolinium-enhanced brain MRI showed abnormal enhancement images, and five of them showed linear perivascular radial enhancement. The modified Rankin scale (mRS) score decreased significantly in most patients after immunotherapy. Two patients with coexisting neural autoantibodies relapsed; however, 15 patients who were followed up successfully had favorable outcomes at the last follow-up. CONCLUSION: Children with autoimmune GFAP astrocytopathy usually have a clinical syndrome of encephalitis/meningoencephalitis with or without myelitis. Except for the linear perivascular radial gadolinium enhancement pattern, hyperintense lesions in the bilateral basal ganglia and thalamus might be another characteristic brain MRI finding of autoimmune GFAP astrocytopathy in children. Although a few patients with coexisting neural autoantibodies might relapse, children with autoimmune GFAP astrocytopathy usually have favorable outcomes after immunotherapy.

MR Imaging Findings in a Large Population of Autoimmune Encephalitis.

BACKGROUND AND PURPOSE: Autoimmune encephalitis is a rare condition in which autoantibodies attack neuronal tissue, causing neuropsychiatric disturbances. This study sought to evaluate MR imaging findings associated with subtypes and categories of autoimmune encephalitis. MATERIALS AND METHODS: Cases of autoimmune encephalitis with specific autoantibodies were identified from the medical record (2009-2019). Cases were excluded if no MR imaging of the brain was available, antibodies were associated with demyelinating disease, or >1 concurrent antibody was present. Demographics, CSF profile, antibody subtype and group (group 1 intracellular antigen or group 2 extracellular antigen), and MR imaging features at symptom onset were reviewed. Imaging and clinical features were compared across antibody groups using χ2 and Wilcoxon rank-sum tests. RESULTS: Eighty-five cases of autoimmune encephalitis constituting 16 distinct antibodies were reviewed. The most common antibodies were anti-N-methyl-D-aspartate (n = 41), anti-glutamic acid decarboxylase (n = 7), and anti-voltage-gated potassium channel (n = 6). Eighteen of 85 (21%) were group 1; and 67/85 (79%) were group 2. The median time between MR imaging and antibody diagnosis was 14 days (interquartile range, 4-26 days). MR imaging had normal findings in 33/85 (39%), and 20/33 (61%) patients with normal MRIs had anti-N-methyl-D-aspartate receptor antibodies. Signal abnormality was most common in the limbic system (28/85, 33%); 1/68 (1.5%) had susceptibility artifacts. Brainstem and cerebellar involvement were more common in group 1, while leptomeningeal enhancement was more common in group 2. CONCLUSIONS: Sixty-one percent of patients with autoimmune encephalitis had abnormal brain MR imaging findings at symptom onset, most commonly involving the limbic system. Susceptibility artifact is rare and makes autoimmune encephalitis less likely as a diagnosis. Brainstem and cerebellar involvement were more common in group 1, while leptomeningeal enhancement was more common in group 2.

Impact of COVID-19 vaccination or infection on disease activity in a radiologically isolated syndrome cohort: The VaxiRIS study.

BACKGROUND: Vaccination in patients with multiple sclerosis (MS) treated with immunosuppressive drugs is highly recommended. Regarding COVID-19 vaccination, no specific concern has been raised. OBJECTIVES: We aimed to evaluate if COVID-19 vaccination or infection increased the risk of disease activity, either radiological or clinical, with conversion to MS in a cohort of people with a radiologically isolated syndrome (RIS). METHODS: This multicentric observational study analyzed patients in the RIS Consortium cohort during the pandemic between January 2020 and December 2022. We compared the occurrence of disease activity in patients according to their vaccination status. The same analysis was conducted by comparing patients' history of COVID-19 infection. RESULTS: No difference was found concerning clinical conversion to MS in the vaccinated versus unvaccinated group (6.7% vs 8.5%, p > 0.9). The rate of disease activity was not statistically different (13.6% and 7.4%, respectively, p = 0.54). The clinical conversion rate to MS was not significantly different in patients with a documented COVID-19 infection versus non-infected patients. CONCLUSION: Our study suggests that COVID-19 infection or immunization in RIS individuals does not increase the risk of disease activity. Our results support that COVID-19 vaccination can be safely proposed and repeated for these subjects.

Metabolic phenotyping of pilomotor seizures in autoimmune encephalitis.

OBJECTIVES: Ictal piloerection (IP) is an uncommon symptom in focal epilepsy and is associated with autoimmune encephalitis (AE). However, the networks involved in AE-associated IP are still unclear. To have a better understanding of IP underlying mechanisms, the current study investigated whole-brain metabolic networks for the analysis of AE-associated IP. METHODS: Patients with AE and IP diagnosed at our Institute between 2018 and 2022 were selected. We then investigated the brain regions associated with AE-associated IP using positron emission tomography (PET). Anatomometabolic changes (interictal 18 F fluorodeoxyglucose PET) in AE patients with IP were compared with those of AE patients of similar age without IP (p-voxel <0.001, uncorrected). RESULTS: Sixteen patients showed significant IP. The overall IP prevalence was 4.09% of patients with AE and 12.9% of patients with limbic encephalitis. The most common autoantibodies were against LGI1 (68.8%) followed by GAD65 (6.3%), NMDA (6.3%), GABAb (6.3%), CASPR2 (6.3%), and antibodies recognizing both GAD65 and mGLUR5 (6.3%). Most patients responded well to immunotherapy. Analysis of the imaging results at the voxel level showed that patients with IP had hypermetabolic changes in the right inferior temporal gyrus, suggesting involvement of this brain region in IP. CONCLUSIONS: Our findings indicate that IP as an uncommon AE-associated manifestations should be recognized. We observed that the metabolic pattern of IP was conspicuous in the right inferior temporal gyrus.

Autoimmune-mediated encephalitis and mimics: A neuroimaging review.

Autoimmune encephalitis is a category of autoantibody-mediated neurological disorders that often presents a diagnostic challenge due to its variable clinical and imaging findings. The purpose of this image-based review is to provide an overview of the major subtypes of autoimmune encephalitis and their associated autoantibodies, discuss their characteristic clinical and imaging features, and highlight several disease processes that may mimic imaging findings of autoimmune encephalitis. A literature search on autoimmune encephalitis was performed and publications from neuroradiology, neurology, and nuclear medicine literature were included. Cases from our institutional database that best exemplify major imaging features were presented.

Typical linear radial periventricular enhancement in a patient with glial fibrillary acidic protein (GFAP) astrocytopathy.

OBJECTIVE: We describe an unusual case of corticosteroid-responsive autoimmune meningoencephalomyelitis with linear perivascular gadolinium enhancement but in the absence of anti- glial fibrillary acidic protein (GFAP) antibodies (ABs) in the cerebral spinal fluid (CSF). METHODS: The patient's clinical symptoms, brain magnetic resonance imaging (MRI) features, serum and CSF analysis and treatment were reviewed. RESULTS: A 47-year-old female experienced a subacute course with bilateral lower limbs weakness, unsteady walking, and dysuria. Brain MRI revealed typical radial perivascular gadolinium enhancement extending from the lateral ventricles to the white matter; MRI spine revealed lesions distributed in the entire spinal cord. Immunohistochemical staining of a brain biopsy revealed CD3+ T cells and CD20+ B cells cuffing around brain vessels, accompanied by CD68+ macrophages. CSF was negative for anti-GFAP ABs while serum was positive for anti-GFAP ABs (1:100). The patient responded well to corticosteroid. CONCLUSIONS: There are no uniform diagnostic criteria for autoimmune GFAP astrocytopathy. Our case suggested the importance of typical MRI findings in the diagnosis of this rare disease. Early treatments are very important to alleviate symptoms.

MRI features and evolution of autoimmune glial fibrillary acidic protein astrocytopathy: A retrospective cross-sectional and longitudinal study.

BACKGROUND: Autoimmune glial fibrillary acidic protein astrocytopathy (AGA) is a relatively novel disease. The early diagnosis of this inflammatory central nervous system (CNS) disorder remains challenging. OBJECTIVES: We aimed to explore the imaging manifestations and evolution of AGA to facilitate its successful diagnosis and monitoring. METHODS: From January 2016 to January 2021, a total of 15 consecutive patients, who were hospitalised in our institution and confirmed AGA clinically, were enrolled in this IRB-approved retrospective study. All clinical features and MRI manifestations were analysed cross-sectionally and longitudinally. Distribution, morphology, enhancement pattern and evolution of AGA lesions were assessed visually and evaluated semi-quantitatively by calculating the burden of disease (BOD) and the signal intensity ratio (SIR). Chi-square, Mann-Whitney U and Kolmogorov-Smirnov Z tests were performed for lesion patterns' statistical comparison. RESULTS: Fever, limb weakness, headache and cognitive impairment were the most common symptoms in AGA. 14 patients were initially misdiagnosed as infection (n = 9), demyelination (n = 4) or infarction (n = 1). The median time interval from onset to confirmed AGA diagnosis was 46 days. Both BOD and SIR progressed in the natural course and were relieved after immunotherapy on MRI. Meningeal enhancement, one of the most common MRI findings in patients with AGA (100%), relieved faster than intraparenchymal enhancement (p <0.001) and peri­ventricular radial linear (PVRL) enhancement (p <0.001) after the initiation of immunotherapy. Non-enhanced lesions had lower BOD (p <0.001) and were relieved slower (p <0.001) than enhanced ones. CONCLUSIONS: MRI provides valuable neuroradiological indicators for the diagnosis and follow-up of AGA. The CNS enhancement patterns (meningeal / PVRL) facilitate the early diagnosis and treatment response monitoring of AGA, while lesion manifestation in the spinal cord contributes to the follow-up. The evolution inconsistency of AGA lesions in different regions may be attributed to the discrepancy within glial fibrillary acidic protein subtypes.

Clinical, neuroradiological, diagnostic and prognostic profile of autoimmune glial fibrillary acidic protein astrocytopathy: A pooled analysis of 324 cases from published data and a single-center retrospective study.

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy is a recently defined autoimmune meningoencephalomyelitis, associated with GFAP-IgG antibody. A pooled analysis of 324 cases from published literature and a retrospective single-center study were performed, firstly reveals the possibility that patients with myelitic lesions respond better to initial immunotherapy, but are prone to relapse, suggesting a more aggressive and long-term immunosuppressive medication for them. Moreover, our results showed using tacrolimus at maintenance stage exhibited a less tendency to relapse, providing a possibly new choice to future clinical treatments.

Autoimmune GFAP astrocytopathy presenting with remarkable CNS hyperexcitability and oculogyric crises.

The autoimmune GFAP astrocytopathy has been associated with meningoencephalomyelitis that usually responds to glucocorticoids. We report a 20-year-old man that developed an acute and severe meningoencephalomyelitis with remarkable CNS hyperexcitability and oculogyric crises. CSF analysis showed hypoglycorrhachia, pleocytosis, elevated ADA, and CSF-immunofluorescence characteristic of autoimmune GFAP astrocytopathy. MRI showed lesions at thalamus, corpus-callosum, dorsal pons and dentate nucleus with associated myelitis. Immunotherapy led to a full recovery, although MRI activity was observed at follow-up. CNS hyperexcitability, typically seen in other immune-mediated syndromes, represents a novel presenting form to be included as part of the clinical spectrum of this entity.

Opsoclonus-myoclonus in Aicardi-Goutières syndrome.

Aicardi-Goutières syndrome (AGS) is a rare genetic neuroinflammatory disorder caused by abnormal upregulation of type 1 interferon signalling. Opsoclonus-myoclonus syndrome is a rare autoimmune phenotype demonstrating a disturbance in the humoral immune response mostly seen in the context of paraneoplastic or postinfectious states, although its pathophysiology is incompletely understood. We report the first three children described with AGS demonstrating transient opsoclonus and myoclonus after irritability and/or developmental regression, suggesting a pathological association. We describe the presentation, clinical features, progress, cerebrospinal fluid (CSF) inflammatory markers, electroencephalogram (EEG), and magnetic resonance imaging (MRI) findings in these children. Two patients had developmental regression but demonstrated a positive response to JAK1/2 inhibition clinically and on serial examination of CSF inflammatory markers. These findings suggest that AGS should be considered in children presenting with opsoclonus-myoclonus, and that the association between AGS and opsoclonus-myoclonus further supports the role of immune dysregulation as causal in the rare neurological phenomenon opsoclonus and myoclonus. What this paper adds There is a phenotypic association between opsoclonus-myoclonus syndrome and Aicardi-Goutières syndrome. There is clinical evidence of immune dysregulation in the pathogenesis of opsoclonus and myoclonus.

Severe diarrhea in a 10-year-old girl with Aicardi-Goutières syndrome due to IFIH1 gene mutation.

Interferon-induced with helicase C domain 1 (IFIH1) is a cytosolic sensor of dsRNA that induces an anti-viral Type I interferon (IFN) state. A gain-of-function mutation in IFIH1 can cause increased Type I IFN activity and is clinically associated with Aicardi-Goutières syndrome (AGS). AGS is a multisystem disease, characterized as an early-onset progressive encephalopathy with basal ganglia calcification and systemic lupus erythematosus-like features. Gastrointestinal manifestation is rare in AGS patients. We described a 10-year-old female patient with a heterozygous IFIH1 gene mutation who presented with gastrointestinal colitis, cystitis and very severe diarrhea as initial major manifestations of AGS. Proteinuria with high titer of antinuclear antibody and anti-double-stranded DNA was found in this patient. She also had growth retardation and a history of seizures (about two episodes each year) but without attacks until 7 years old. Serum cytokines detected by flow cytometry indicated extremely high level of interleukin 6 (1970.1 pg/ml) and IFN-α (204.1 pg/ml). A contrast-enhanced CT scan of the whole abdomen and an intestinal hydro-MRI indicated that the walls of her stomach, small bowel, colon, and bladder were in various degrees of edema and thickened states. Whole exome sequencing analysis indicated that she harbors an IFIH1 heterozygous mutation (c.2336G > A (p.R779H)) in both blood and intestinal samples. Abundant inflammatory cells infiltration into the intestinal epithelium was observed by immunohistochemical staining. Positive staining of caspase 4 and caspase 5 suggested that the signaling pathway of pyroptosis was involved in the mechanism of intestinal inflammation in AGS. Diarrhea was significantly improved after steroids and intravenous immunoglobulin treatments. Gastrointestinal colitis and cystitis can be rare manifestations of AGS with IFIH1 mutation. Caspase and its related inflammasome pathway may involve in the pathogenesis of AGS.

Age-dependent favorable visual recovery despite significant retinal atrophy in pediatric MOGAD: how much retina do you really need to see well?

BACKGROUND: To investigate age-related severity, patterns of retinal structural damage, and functional visual recovery in pediatric and adult cohorts of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) optic neuritis (ON). METHODS: All MOGAD patients from the 5 participating centers were included. Patients with initial manifestation <18 years were included in the pediatric (MOGADped) cohort and patients with ≥18 years in the adult (MOGADadult) cohort. For patients with MOGAD ON, examinations at least ≥6 months after ON onset were included in the analyses. Using spectral domain optical coherence tomography (SD-OCT), we acquired peripapillary retinal nerve fiber layer thickness (pRNFL) and volumes of combined ganglion cell and inner plexiform layer (GCIPL). High- and 2.5% low-contrast visual acuity (HCVA, LCVA) and visual-evoked potentials (VEP) were obtained. RESULTS: Twenty MOGADped (10.3±3.7 years, 30 MOGAD ON eyes) and 39 MOGADadult (34.9±11.6 years, 42 MOGAD ON eyes) patients were included. The average number of ON episodes per ON eye was similar in both groups (1.8±1.3 and 2.0±1.7). In both pediatric and adult MOGAD, ON led to pronounced neuroaxonal retinal atrophy (pRNFL: 63.1±18.7 and 64.3±22.9 µm; GCIPL: 0.42±0.09 and 0.44±0.13 mm3, respectively) and moderate delay of the VEP latencies (117.9±10.7 and 118.0±14.5 ms). In contrast, visual acuity was substantially better in children (HCVA: 51.4±9.3 vs. 35.0±20.6 raw letters, p=0.001; LCVA: 22.8±14.6 vs. 13.5±16.4, p=0.028). Complete visual recovery (HCVA-logMAR 0.0) occurred in 73.3% of MOGADped and 31% MOGADadults ON eyes, while 3.3% and 31% demonstrated moderate to severe (logMAR > 0.5) visual impairment. Independent of retinal atrophy, age at ON onset significantly correlated with visual outcome. CONCLUSION: Pediatric MOGAD ON showed better visual recovery than adult MOGAD ON despite profound and almost identical neuroaxonal retinal atrophy. Age-related cortical neuroplasticity may account for the substantial discrepancy between structural changes and functional outcomes.