A comparative study on anti-MOG and anti-AQP4 associated optic neuritis following mild COVID-19: insights from a Chinese single-center experience.

Background: Research on the relationship between mild COVID-19 and the subsequent development of isolated optic neuritis (ON) with antibodies specific to myelin oligodendrocyte glycoprotein (MOG-ON) and aquaporin 4 (AQP4-ON) is limited, particularly case-control studies that directly compare these conditions within the same affected population. Methods: A retrospective analysis of initial MOG-ON and AQP4-ON cases during the COVID-19 peak and subsequent months. Patients were classified as possible COVID-19 related ON (PCRON) or non-COVID-19 related ON (NCRON). The study compared epidemiology, comorbidities, and clinical features between these groups. Results: Patients with MOG-ON tended to develop ON symptoms closer in time to a mild COVID-19 infection compared to those with AQP4-ON (6.87 ± 6.25 weeks vs. 11.06 ± 5.84 weeks; p = 0.038), a significantly higher proportion of patients with MON-ON developing symptoms within 6 weeks after COVID-19 compared to those with AQP4-ON (15/23 [65.2%] vs. 5/17 [29.4%]; p = 0.025). Comparing MOG-ON and AQP4-ON patients, MOG-ON patients were more likely to have a recent infection before ON onset (73.1% vs. 30%; p = 0.007) and had better peak and post-treatment visual acuity (p = 0.01; p < 0.001). In contrast, AQP4-ON patients frequently showed comorbid connective tissue diseases (30.0% vs. 0%, p = 0.004) and antinuclear antibody abnormalities (40.0% vs. 7.7%, p = 0.012). Among MOG-ON patients, PCRON had increased rates of atherosclerotic vascular diseases (AVDs) (53.3% vs. 9.1%, p = 0.036), phospholipid antibody abnormalities (60.0% vs. 18.2%, p = 0.04), and bilateral visual impairment (66.7% vs. 9.1%, p = 0.005). Multivariate analysis pinpointed AVDs (OR = 15.21, p = 0.043) and bilateral involvement (OR = 25.15, p = 0.015) as independent factors related to COVID-19 associated MOG-ON, with both being good discriminators for PCRON (AUC = 0.879). No differences were found between the PCRON and NCRON groups in AQP4-ON patients. Conclusion: Mild COVID-19 is more likely associated with MOG-ON than AQP4-ON. MOG-ON that develops within 6 weeks following a COVID-19 infection may be associated with the COVID-19 infection. AVDs may have a synergistic effect on MOG-ON in patients with COVID-19, which warrants further investigation. COVID-19 related MOG-ON often affects both eyes, and acute visual function damage can be severe, but generally has a good prognosis.

Successful treatment with efgartigimod as an add-on therapy in acute attack of anti-AQP4 antibody-positive NMOSD: a case report.

BACKGROUND: Neuromyelitis Optica Spectrum Disorder (NMOSD) is an autoimmune demyelinating disease characterized by recurrent myelitis and optic neuritis. It is associated with high rates of relapse and disability. The main treatment strategies for acute attacks include intravenous methylprednisolone pulse (IVMP) treatment and rescue treatment with plasma exchange (PLEX). Recently, the blockade of neonatal Fc receptor (FcRn)-IgG interaction has gained momentum as a therapeutic strategy. Efgartigimod, the first approved FcRn inhibitor for treating generalized myasthenia gravis, has shown impressive safety, efficacy, and tolerability, and is being regarded as "PLEX in a bottle". CASE DESCRIPTION: We report a 65-year-old female patient who was diagnosed with anti-AQP4 antibody positive NMOSD. Add-on treatment with efgartigimod to IVMP and intravenous immunoglobulin (IVIG) at the second acute relapse showed favorable results. CONCLUSION: This case suggests that efgartigimod is a potentially effective add-on therapy in acute attacks of AQP4-IgG-positive NMOSD.

Optic Nerve Imaging in Multiple Sclerosis and Related Disorders.

Optic neuritis is a common feature in multiple sclerosis and in 2 other autoimmune demyelinating disorders such as aquaporin-4 IgG antibody-associated neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody-associated disease. Although serologic testing is critical for differentiating these different autoimmune-mediated disorders, MR imaging, which is the preferred imaging modality for assessing the optic nerve, can provide valuable information, suggesting a specific diagnosis and guiding the appropriate serologic testing.

Case report: Overlap syndrome of neuromyelitis optica spectrum disorder with anti-Argonaute antibodies.

Aquaporin-4 antibodies (AQP4-Abs) are a diagnostic marker for patients with a demyelinating disease called neuromyelitis optica spectrum disorder (NMOSD). Anti-Argonaute antibodies (AGO-Abs) present as potential biomarkers of the overlap syndrome between NMOSD and other autoimmune diseases. In this paper, we present the case of an adult woman with numbness, tingling, and burning sensations in her arms and subsequent bilateral internuclear ophthalmoplegia. Brain-cervical-thoracic magnetic resonance imaging (MRI) showed T2 hyperintensities in the dorsal brainstem and around the midbrain aqueduct and longitudinally transverse myelitis with homogeneous enhancement on gadolinium-enhanced MRI. The contemporaneous detection of AQP4- and AGO-Abs led to a definite diagnosis of overlap syndrome of NMOSD with AGO-Abs. The patient was treated with immunosuppressive agents, including corticosteroids and immunoglobulins, and achieved remission. This case highlights a novel phenotype of NMOSD with AGO-Abs overlap syndrome, which presents with relapsing brainstem syndrome and longitudinally extensive myelitis with acute severe neurological involvement. The promising prognosis of the disease could serve as a distinct clinical profile. Broad screening for antibodies against central nervous system autoimmune antigens is recommended in suspected patients with limited or atypical clinical manifestations.

Case report: Transition from anti-CD20 therapy to inebilizumab for 14 cases of neuromyelitis optica spectrum disorder.

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune disorder of the central nervous system characterized by recurrent, disabling attacks that affect the optic nerve, spinal cord, and brain/brainstem. While rituximab, targeting CD20-positive B-cells, is used as an off-label therapy for NMOSD, some patients continue to exhibit breakthrough attacks and/or adverse reactions. Inebilizumab, a humanized and glycoengineered monoclonal antibody targeting CD19-positive B-cells, has been FDA approved for the treatment of NMOSD in adult patients who are anti-aquaporin-4 (AQP4) antibody positive. Given the limited real-world data on the efficacy and safety of inebilizumab, especially in those transitioning from rituximab, a retrospective chart review was conducted on 14 NMOSD patients from seven centers. Of these, 71.4% (n = 10) experienced a combined 17 attacks during rituximab treatment, attributed to either breakthrough disease (n = 10) or treatment delay (n = 7). The mean duration of rituximab treatment was 38.4 months (3.2 years). Notably, no subsequent attacks were observed during inebilizumab treatment [mean duration of inebilizumab treatment was 19.3 months (1.6 years)], underscoring its potential as an effective treatment for NMOSD. Our data suggest that inebilizumab provides clinical benefit with effective disease control and a favorable safety profile for patients transitioning from rituximab.

Double Seronegative Neuromyelitis Optica Spectrum Disorder with Longitudinally Extensive Transverse Myelitis and Optic Neuritis: A Challenging Case Report.

Neuromyelitis optica spectrum disorder (NMOSD) is a rare antibody-mediated neuroinflammatory disease of the central nervous system, typically manifesting in the optic nerves, spinal cord, and other regions of the central nervous system. We hereby report a case of a 16-year-old girl who presented with a six-month history of transverse myelitis with an acute episode of bilateral retrobulbar optic neuritis. MRI revealed patchy contrast enhancements over bilateral retrobulbar intraorbital optic nerves together with long-segment spinal cord hyperintensities (C2 to T2 level). Visual evoked potential testing during the acute presentation showed the absence of P100 bilaterally. However, both serum AQP4-IgG and MOG-IgG were reported to be negative. Despite remarkable improvement in bilateral optic nerve functions, she continued to have disabling bilateral lower limb spasticity, contractures, and loss of bilateral lower limb sensation after five cycles of plasma exchange. This case summarizes the challenges to diagnosing double seronegative NMOSD and its immediate therapeutic significance.

Optic chiasm involvement in multiple sclerosis, aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein-associated disease.

BACKGROUND: Optic neuritis (ON) is a common feature of inflammatory demyelinating diseases (IDDs) such as multiple sclerosis (MS), aquaporin 4-antibody neuromyelitis optica spectrum disorder (AQP4 + NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). However, the involvement of the optic chiasm (OC) in IDD has not been fully investigated. AIMS: To examine OC differences in non-acute IDD patients with (ON+) and without ON (ON-) using magnetisation transfer ratio (MTR), to compare differences between MS, AQP4 + NMOSD and MOGAD and understand their associations with other neuro-ophthalmological markers. METHODS: Twenty-eight relapsing-remitting multiple sclerosis (RRMS), 24 AQP4 + NMOSD, 28 MOGAD patients and 32 healthy controls (HCs) underwent clinical evaluation, MRI and optical coherence tomography (OCT) scan. Multivariable linear regression models were applied. RESULTS: ON + IDD patients showed lower OC MTR than HCs (28.87 ± 4.58 vs 31.65 ± 4.93; p = 0.004). When compared with HCs, lower OC MTR was found in ON + AQP4 + NMOSD (28.55 ± 4.18 vs 31.65 ± 4.93; p = 0.020) and MOGAD (28.73 ± 4.99 vs 31.65 ± 4.93; p = 0.007) and in ON- AQP4 + NMOSD (28.37 ± 7.27 vs 31.65 ± 4.93; p = 0.035). ON+ RRMS had lower MTR than ON- RRMS (28.87 ± 4.58 vs 30.99 ± 4.76; p = 0.038). Lower OC MTR was associated with higher number of ON (regression coefficient (RC) = -1.15, 95% confidence interval (CI) = -1.819 to -0.490, p = 0.001), worse visual acuity (RC = -0.026, 95% CI = -0.041 to -0.011, p = 0.001) and lower peripapillary retinal nerve fibre layer (pRNFL) thickness (RC = 1.129, 95% CI = 0.199 to 2.059, p = 0.018) when considering the whole IDD group. CONCLUSION: OC microstructural damage indicates prior ON in IDD and is linked to reduced vision and thinner pRNFL.

Brain and spinal cord atrophy in NMOSD and MOGAD: Current evidence and future perspectives.

Neuromyelitis optica spectrum disorder (NMOSD) is a severe form of inflammation of the central nervous system (CNS) including acute myelitis, optic neuritis and brain syndrome. Currently, the classification of NMOSD relies on serologic testing, distinguishing between seropositive or seronegative anti-aquaporin-4 antibody (AQP4) status. However, the situation has recently grown more intricate with the identification of patients exhibiting the NMOSD phenotype and myelin oligodendrocyte glycoprotein antibodies (MOGAD). NMOSD is primarily recognized as a relapsing disorder; MOGAD can manifest with either a monophasic or relapsing course. Significant symptomatic inflammatory CNS injuries with stability in clinical findings outside the acute phase are reported in both diseases. Nevertheless, recent studies have proposed the existence of a subclinical pathological process, revealing longitudinal changes in brain and spinal cord atrophy. Within this context, we summarise key studies investigating brain and spinal cord measurements in adult NMOSD and MOGAD. We also explore their relationship with clinical aspects, highlight differences from multiple sclerosis (MS), and address future challenges. This exploration is crucial for determining the presence of chronic damage processes, enabling the customization of therapeutic interventions irrespective of the acute phase of the disease.

Case report: Tolosa-Hunt syndrome-expanding the neuromyelitis optica spectrum disorder phenotype?

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune astrocytopathy caused by the autoantibody of aquaporin-4 (AQP4). Herein, we report a case of Tolosa-Hunt syndrome presenting with abducens palsy and AQP4 antibodies. This was a rare case of AQP4-immunoglobulin G seropositivity in a patient with Tolosa-Hunt syndrome. Our findings may expand the clinical phenotype of NMOSD and indicate that clinicians should consider testing for AQP4 antibodies in patients with Tolosa-Hunt syndrome.

Inhibition of repulsive guidance molecule-a ameliorates compromised blood-spinal cord barrier integrity associated with neuromyelitis optica in rats.

The influx of pathogenic aquaporin-4 antibodies (AQP4-Abs) across the blood-spinal cord barrier (BSCB) is crucial for the development and exacerbation of neuromyelitis optica (NMO). We examined whether prophylactic intravenous administration of anti-repulsive guidance molecule-a antibodies (RGMa-Abs) has disease-modifying effects on BSCB dysfunction using an NMO model elicited by peripheral administration of AQP4-Abs to rats. RGMa-Ab treatment attenuated the acute exacerbation of perivascular astrocytopathy in the spinal cord and clinical symptoms, which were highly correlated with neurofilament light chain levels in both the cerebrospinal fluid (CSF) and serum. Additionally, RGMa-Ab treatment suppressed the expression of proinflammatory cytokines/chemokines and the infiltration of inflammatory cells into the spinal cord. CSF analysis of NMO rats revealed that RGMa-Ab treatment improved the CSF/serum albumin ratio and suppressed AQP4-Abs influx. RGMa inhibition using RGMa-Abs is suggested as a potential therapeutic option for BSCB dysfunction associated with NMO.

Analysis of the initial orbital MRI in aquaporin-4 antibody-positive optic neuritis (AQP4-ON): lesion location and lesion length can be predictive of visual prognosis.

PURPOSE: Despite mounting evidence indicating that aquaporin-4 antibody-positive optic neuritis (AQP4-ON) presents a less favorable prognosis than other types of optic neuritis, there exists substantial heterogeneity in the prognostic outcomes within the AQP4-ON cohort. Considering the persistent debate over the role of MRI in assessing the prognosis of optic neuritis, we aim to investigate the correlation between the MRI appearance and long-term visual prognosis in AQP4-ON patients. METHODS: We retrospectively reviewed the ophthalmological and imaging data of AQP4-ON patients admitted to our Neuro-ophthalmology Department from January 2015 to March 2018, with consecutive follow-up visits for a minimum of 3 years. RESULTS: A total of 51 AQP4-ON patients (59 eyes) meeting the criteria were enrolled in this research. After assessing the initial orbital MR images of each patient at the first onset, we observed the involvement of the canalicular segment (p < 0.001), intracranial segment (p = 0.004), optic chiasm (p = 0.009), and the presence of LEON (p = 0.002) were significantly different between recovery group and impairment group. For quantitative measurement, the length of the lesions is significantly higher in the impairment group (20.1 ± 9.3 mm) than in the recovery group (12.5 ± 5.3 mm) (p = 0.001). CONCLUSION: AQP4-ON patients with involvement of canalicular, intracranial segment and optic chiasm of the optic nerve, and the longer range of lesions threaten worse vision prognoses. Timely MR examination during the initial acute phase can not only exclude the intracranial or orbital mass lesions but also indicate visual prognosis in the long term.

Prevalence of serum MOG antibody and AQP4 antibody in optic neuritis after SARS-CoV-2 infection.

Purpose: To evaluate the prevalence of serum myelin oligodendrocyte glycoprotein antibody (MOG-Ab) and aquaporin-4 antibody (AQP4-Ab) in optic neuritis (ON) patients after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection by cell-based indirect immunofluorescence assay (CBA). Methods: In this prospective case series study, 35 patients clinically diagnosed as ON and laboratory-confirmed SARS-CoV-2 infection from 8 December 2022 to 8 February 2023 were included. All patients' clinical and laboratory data were collected and analyzed. Results: The mean age of the 35 patients (46 eyes) was 38.2 years (ranging from 6 to 69 years), and 17 cases were female patients. Thirty-three and two cases showed positive SARS-CoV-2 RNA test results before or shortly after ON onset, respectively. ON occurred unilaterally in 24 cases and bilaterally in 11 cases. Ophthalmic examination revealed swollen optic disc in 37 eyes, normal optic disc in 6 eyes, and temporally or wholly paled optic disc in 3 eyes. CBA revealed seropositive MOG-Ab in 10 cases and AQP4-Ab in 2 cases, respectively, of which 2 AQP4-Ab-seropositive cases and 1 MOG-Ab-seropositive case had a past medical history of ON. Most ON patients showed a rapid and dramatic response to pulse steroid therapy. The median of BCVA at the onset and at the last follow-up was 20/500 (ranging from light perception to 20/20) and 20/67 (ranging from counting fingers to 20/20), respectively. Conclusion: Serum MOG-Ab and AQP4-Ab were detected in 28.6% (10/35) and 5.7% (2/35) ON cases after SARS-CoV-2 infection. SARS-CoV-2 infection may trigger an onset or a relapse of ON, as well as the production of MOG-Ab.

Anti-glial fibrillary acidic protein antibody and anti-aquaporin-4 antibody double-positive neuromyelitis optica spectrum disorder: A case report.

BACKGROUND: A case of neuromyelitis optica spectrum disorder (NMOSD) with positive cerebrospinal fluid (CSF) anti-aquaporin-4 antibody (AQP4-IgG) and anti-glial fibrillary acidic protein IgG (GFAP-IgG) at the time of relapse was reported. The exact roles of GFAP-IgG in NMOSD are not fully understood and are the subject of ongoing research. This study revealed the possible connection between GFAP-IgG and the occurrence or development of diseases. CASE SUMMARY: A 19-year-old woman was admitted to the hospital due to a constellation of symptoms, including dizziness, nausea, and vomiting that commenced 1 year prior, reoccurred 2 mo ago, and were accompanied by visual blurring that also began 2 mo ago. Additionally, she presented with slurred speech and ptosis, both of which emerged 1 mo ago. Notably, her symptoms deteriorated 10 d prior to admission, leading to the onset of arm and leg weakness. During hospitalization, magnetic resonance imaging showed high T2-fluid attenuated inversion recovery signals, and slightly high and equal diffusion-weighted imaging signals. The serum antibody of AQP4-IgG tested positive at a dilution of 1:100. CSF antibody testing showed positive results for GFAP-IgG at a dilution of 1:10 and AQP4-IgG at a dilution of 1:32. Based on these findings, the patient was diagnosed with NMOSD. She received intravenous methylprednisolone at a daily dose of 500 mg for 5 d, followed by a tapering-off period. Afterward, the rate of reduction was gradually slowed down and the timely use of immunosuppressants was implemented. CONCLUSION: The CFS was slightly GFAP-IgG-positive during the relapse period, which can aid in the diagnosis and treatment of the disease.

Efficacy and safety of inebilizumab in Asian participants with neuromyelitis optica spectrum disorder: Subgroup analyses of the N-MOmentum study.

BACKGROUND: Inebilizumab, an anti-CD19 B cell-depleting antibody, reduced the risk of a neuromyelitis optica spectrum disorder (NMOSD) attack, disability worsening, magnetic resonance imaging (MRI) lesion activity, and disease-related hospitalizations in participants with NMOSD in the N-MOmentum study (NCT02200770). However, the efficacy and safety outcomes of inebilizumab specific to an Asian population were not fully reported. Therefore, subgroup analyses of the N-MOmentum study were conducted post hoc to evaluate the efficacy and safety of inebilizumab in Asian participants with NMOSD. METHODS: The N-MOmentum study was a multicenter, double-blind, randomized, placebo-controlled phase 2/3 trial with an open-label extension period (OLP). In the subgroup analyses, data from Asian participants from the N-MOmentum study were compared with those of non-Asian participants. Eligible participants were randomly allocated (3:1) to receive 300 mg intravenous (IV) inebilizumab or placebo on Days 1 and 15. Participants who had an NMOSD attack or completed the randomized controlled period (RCP) could enter the OLP, where they received inebilizumab for ≥2 years. All participants who entered the OLP received inebilizumab 300 mg IV every 6 months. RESULTS: Overall, 230 participants received treatment (174 received inebilizumab and 56 received placebo), of whom 47 were Asian (39 received inebilizumab and 8 received placebo). Baseline characteristics were similar between the Asian and non-Asian subgroups, except for disease duration, annualized relapse rate prior to randomization in this study, and previous maintenance therapy. In the Asian subgroup, the risk of NMOSD attacks was reduced with inebilizumab versus placebo (hazard ratio, 0.202) and the attack-free rate at 28 weeks was 82.1% with inebilizumab versus 37.5% with placebo, in the 6-month RCP. NMOSD attack rates were comparable between the Asian and non-Asian subgroups. In the Asian subgroup, the rates of Expanded Disability Status Scale worsening from baseline, active MRI lesions, and disease-related hospitalizations tended to be lower in the inebilizumab group than in the placebo group; similar results were shown in the non-Asian subgroup. For long-term efficacy and safety (RCP and OLP), the annualized adjudicated NMOSD attack rate in Asian participants treated with inebilizumab was reduced (0.096) compared with that at baseline (1.04), with a mean follow-up period of inebilizumab treatment of 3.38 years, which was consistent with the results in the non-Asian subgroup. The risk of NMOSD attack decreased with prolonged duration of treatment in both the inebilizumab/inebilizumab and placebo/inebilizumab groups in the Asian and non-Asian subgroups. The incidence of treatment-emergent adverse events (TEAEs) was similar between the Asian and non-Asian subgroups. In the Asian and non-Asian subgroups, 15.2% and 35.2% of participants, respectively, had at least one serious TEAE and/or Grade ≥3 TEAE during long-term therapy. No deaths occurred in the Asian subgroup whereas three deaths occurred in the non-Asian subgroup. CONCLUSION: Inebilizumab reduced the risk of an NMOSD attack, progression of disability, MRI lesion activity, and disease-related hospitalizations in Asian participants with NMOSD. The efficacy of inebilizumab in reducing NMOSD attacks continued without any unexpected safety signals or concerns during long-term use in Asian participants.

Causal associations between prodromal infection and neuromyelitis optica spectrum disorder: A Mendelian randomization study.

BACKGROUND AND PURPOSE: Prodromal infections are associated with neuromyelitis optica spectrum disorder (NMOSD), but it remains unclear which type of infection has a causal association with NMOSD. We aimed to explore the causal associations between four herpesvirus infections (chickenpox, cold sores, mononucleosis and shingles) and NMOSD, as well as between other types of infections and NMOSD. METHODS: For data on infections, we used the genome-wide association study (GWAS) summary statistics from the 23andMe cohort. For outcomes, we used the GWAS data of participants of European ancestry, including 215 NMOSD patients (132 anti-aquaporin-4 antibody [AQP4-ab]-positive patients and 83 AQP4-ab-negative patients) and 1244 normal controls. Single-nucleotide polymorphism (SNP) identification and two-sample Mendelian randomization (MR) analyses were then performed. RESULTS: In the 23andMe cohort, we identified one SNP for chickenpox (rs9266089 in HLA-B gene), one SNP for cold scores (rs885950 in the POU5F1 gene), one SNP for mononucleosis (rs2596465 in the HCP5 gene), and three SNPs for shingles (rs2523591 in the HLA-B gene; rs7047299 in the IFNA21 gene; rs9260809 in the MICD gene). The association between cold sores and AQP4-ab-positive NMOSD reached statistical significance (odds ratio [OR] 745.318; 95% confidence interval [CI] 22.176, 25,049.53 [p < 0.001, Q < 0.001]). The association between shingles and AQP4-ab-positive NMOSD was also statistically significant (OR 21.073; 95% CI 4.271, 103.974 [p < 0.001, Q < 0.001]). No significant association was observed between other infections and AQP4-ab-positive or AQP4-ab-negative NMOSD. CONCLUSION: These findings suggest there are positive associations between cold sores and shingles and AQP4-ab-positive NMOSD, indicating there may be causal links between herpes simplex virus and varicella-zoster virus infection and AQP4-ab-positive NMOSD.

Long-term safety and effectiveness of eculizumab in patients with aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder: a 2-year interim analysis of post-marketing surveillance in Japan.

Background: The terminal complement C5 inhibitor eculizumab is approved in Japan for relapse prevention in aquaporin-4 antibody-positive (AQP4+) neuromyelitis optica spectrum disorder (NMOSD) and is undergoing mandatory post-marketing surveillance (PMS) of clinical use. Objectives: The objective of the study is to assess the real-world, long-term safety and effectiveness of eculizumab in Japanese patients with AQP4+ NMOSD. Design: Regulatory-mandated PMS analysis implemented as an all-case surveillance of all patients with AQP4+ NMOSD who have been treated with eculizumab in Japan since its approval in November 2019. Methods: This PMS interim analysis assessed the safety and effectiveness of eculizumab in Japanese patients with AQP4+ NMOSD from November 2019 to April 2022. Results: Of 147 patients treated with eculizumab who consented to publication, 71 had at least one case report form collected and locked at the interim analysis data cut-off, constituting the safety analysis set; three patients from PREVENT (NCT01892345) were excluded from the effectiveness analysis set. Twelve and 10 patients in the safety and effectiveness analysis sets discontinued, respectively. In the safety analysis set, 67/71 patients (94.4%) were female, mean illness duration was 6.8 [standard deviation (SD): 6.2] years, mean age at eculizumab initiation was 50.7 (SD: 13.3) years, and mean eculizumab treatment duration was 44.6 (SD: 23.7) weeks. At diagnosis of NMOSD, 34/71 patients (47.9%) and 35/71 patients (49.3%) in the safety analysis set had symptoms of optic neuritis and transverse myelitis, respectively. In the safety analysis set, 19/71 patients (26.8%) reported adverse events, 10/71 (14.1%) reported adverse drug reactions (ADRs), and 7/71 (9.9%) reported serious ADRs; no meningococcal infections were observed. In the effectiveness analysis set, 64/68 patients (94.1%) were female, mean disease duration was 6.9 (SD: 6.3) years, mean age at eculizumab initiation was 50.6 (SD: 13.2) years, and 27/68 (39.7%) were tested for C5 genetic polymorphism (all negative). In the 2 years before eculizumab, 51/68 patients (75.0%) experienced relapse. Relapse rate was 0.02/patient-year after eculizumab initiation versus 0.74/patient-year in the 2 years before eculizumab. Overall, 37/68 patients (54.4%) were prescribed immunosuppressants in the 6 months before and 19/40 (47.5%) in the 6-12 months after starting eculizumab treatment. The proportion of patients taking >10 mg/day of prednisolone decreased from 45.6% at 24-20 weeks before to 23.1% and 0% at 48-52 and 100-104 weeks after eculizumab, respectively. Conclusion: This article reports interim PMS data for Japanese patients and provides updated real-world evidence for the safety of eculizumab and its effectiveness at preventing relapses in patients with AQP4+ NMOSD. Safety and effectiveness results are consistent with those from PREVENT.

Late-Onset Neuromyelitis Optica Spectrum Disorder Mimicking a Non-Arteritic Anterior Ischemic Optic Neuropathy-Case Report.

A 60-year-old white woman presented to the emergency department with painless decrease of visual acuity in the left eye (LE). The diagnosis of a non-arteritic anterior ischemic optic neuropathy in the LE was established based on the clinical picture and the results of static perimetry, fluorescein angiography, visual evoked potential, and magnetic resonance imaging (MRI) of the brain and orbit. Six months later, the patient reported visual impairment in the right eye (RE). Best corrected visual acuity (BCVA) in the RE was 5/10. Gadolinium-enhanced MRI showing inflammation of both optic nerves and the optic chiasm in correlation with positivity for immunglobulin G antibody against aquaporin-4 led to the diagnosis of late-onset neuromyelitis optica spectrum disorder. High-dose intravenous methylprednisolone therapy followed by oral tapering was administered and oral azathioprine was started to reduce the risk of further relapse. At discharge, BCVA was 5/5 in the RE. The patient remains under the care of neurology and ophthalmology clinics, with no recurrences for two years. The possibility of neuromyelitis optica spectrum disorder with optic neuritis in older patients is important in the differential diagnosis of ischemic optic neuropathy.

Case Report: Severe rebound after withdrawal of fingolimod in a patient with neuromyelitis optica spectrum disorder.

Purpose: Fingolimod, an oral treatment for relapsing-remitting multiple sclerosis (RRMS), has been associated with a significant rebound in disease activity after therapy cessation. We described a patient with neuromyelitis optica spectrum disorder (NMOSD) who was previously diagnosed with RRMS and experienced fatal rebound syndrome after cessation of fingolimod. Case report: A 54-year-old woman, previously diagnosed with RRMS, experienced relapse after orthopedic surgery. The diagnosis was later revised to NMOSD based on a positive aquaporin-4 antibody. Three weeks after converting the immunomodulator from fingolimod to azathioprine, severe disease reactivation was observed. Considering the multiple new and enlarging magnetic resonance imaging lesions, the temporal relationship between fingolimod cessation and symptom onset, and the relatively low possibility of disease reactivation within a short time, the diagnosis of fingolimod withdrawal syndrome was proposed. Although immediate steroid pulse therapy and plasma exchange were performed, the patient eventually died owing to a fulminant clinical course. Conclusion: Fingolimod withdrawal syndrome is well known in patients with multiple sclerosis (MS). It can also occur in patients with NMOSD. Recognizing patients with NMOSD who present with MS-like manifestations, and avoiding drugs that may be harmful to patients with NMOSD, are important.

A comparative analysis of demographic, clinical and imaging features of myelin oligodendrocyte glycoprotein antibody positive, aquaporin 4 antibody positive, and double seronegative demyelinating disorders - An Indian tertiary care center prospective study.

Objectives: The aim of the study was to study the demographical, clinical, radiological features, and outcome of anti-myelin oligodendrocyte glycoprotein (MOG) antibody spectrum disorder and compare these features with patients negative for anti-MOG antibody. MOG antibody-associated disease (MOGAD) and aquaporin-4 (AQP4) antibody-related diseases are immunologically distinct pathologies. Our aim was to compare the clinical and radiological features of MOG antibody-related diseases with AQP4 antibody-related diseases and seronegative demyelinating diseases (Non-multiple sclerosis). Materials and Methods: This was a prospective and cohort study conducted at an apex tertiary care institute in the northern part of India from Jan 2019 to May 2021. We compared clinical, laboratory, and radiological findings of patients with MOGAD, AQP4 antibody-related diseases, and seronegative demyelinating disease. Results: There were a total of 103 patients - 41 patients of MOGAD, 37 patients of AQP4 antibody-related diseases and 25 seronegative demyelinating disease. Bilateral optic neuritis was the most frequent phenotype in patients with MOGAD (18/41) whereas myelitis was the most common phenotype in the AQP4 (30/37) and seronegative groups (13/25). Cortical, juxtacortical lesions, anterior segment optic neuritis, optic sheath enhancement, and conus involvement in myelitis were radiological findings that separated MOGAD from AQP4 related diseases. Nadir Expanded Disability Status Scale (EDSS) and visual acuity were similar across the groups. Last follow-up EDSS was significantly better in the MOG antibody group as compared to AQP4 antibody group (1 [0-8] vs. 3.5 [0-8]; P = 0.03). Encephalitis, myelitis, and seizures were more common in the younger population (<18 vs. >18 years) in MOGAD (9 vs. 2, P = 0.001; 9 vs. 7, P = 0.03; 6 vs. 0, P = 0.001). Conclusion: We identified several clinical and radiological features that can help physicians to distinguish MOGAD from AQP4-immunoglobulin G+neuromyelitis optica spectrum disorder. Differentiation is vital as treatment response might vary among both groups.