Bidirectional degeneration in the visual pathway in neuromyelitis optica spectrum disorder (NMOSD).

OBJECTIVE: This study aims to investigate whether bidirectional degeneration occurs within the visual pathway and, if so, the extent of such changes in neuromyelitis optica spectrum disorder (NMOSD). METHODS: In total, 36 NMOSD and 24 healthy controls (HCs) were enrolled. Three-dimensional T1-weighted magnetic resonance imaging (MRI) and diffusion tensor imaging were used to analyze damage to the posterior visual pathway. Damage to the anterior visual pathway was measured by optical coherence tomography. RESULTS: In total, 24 NMOSD with prior optic neuritis (NMOON) patients showed significant reduction of peripapillary retinal nerve fiber layer, inner and outer retinal thickness, lateral geniculate nucleus volume, primary visual cortex volume, and decreased integrity of optic radiations, compared with 12 NMOSD without prior optic neuritis (NMONON) patients and 24 HCs. In NMONON, only the inner retinal thickness and the integrity of optic radiations were significantly reduced in comparison with HCs. Moreover, patients with optic neuritis showed severe bidirectional degeneration, the loss of the RNFL was greater than the atrophy of V1. CONCLUSION: Our study indicated the presence of trans-synaptic degeneration in NMOSD. Damage to the inner retina and optic radiations can be observed even in NMONON. After an episode of optic neuritis, the anterior visual pathway damage is greater than the posterior visual pathway damage.

Optical Coherence Tomography Reveals Longitudinal Changes in Retinal Damage Under Different Treatments for Neuromyelitis Optica Spectrum Disorder.

Background: Progressive retinal neuroaxonal damage after acute optic neuritis may occur in neuromyelitis optica spectrum disorder (NMOSD). However, it is unclear if treatments used to prevent attacks influence neurodegeneration. Objectives: We aimed to investigate retinal damage in patients treated with disease-modifying drugs in a longitudinal study. Methods: We retrospectively included 50 patients with aquaporin 4-antibody-seropositive NMOSD. Peripapillary retinal nerve fiber layer (pRNFL) thickness, macular ganglion cell complex (mGCC) thickness, total macular volume (TMV), and optic disc measures were acquired by spectral domain optical coherence tomography in patients treated with tocilizumab, rituximab, and azathioprine. Results: Longitudinally, in eyes with a history of ON (NMOSDON+), we observed annual thinning of mGCC [tocilizumab: -1.77 (-3.44, -0.09) µm, p = 0.041; rituximab: -2.03 (-3.58, -0.48) µm, p = 0.017; azathioprine: -1.79 (-2.22, -1.37) µm, p < 0.001], and pRNFL [tocilizumab: -2.07 (-0.75, -3.39) µm, p = 0.005; rituximab: -2.18 (-0.36, -4.00) µm, p = 0.023; azathioprine: -2.37 (-0.98, -3.75) µm, p = 0.003], reduced TMV [tocilizumab: -0.12 (-0.22, -0.01) mm3, p = 0.028; rituximab: -0.15 (-0.21, -0.08) mm3, p = 0.001; azathioprine: -0.12 (-0.20, -0.04) mm3, p = 0.006], and increased cup area [tocilizumab: 0.08 (-0.01, 0.16) mm2, p = 0.010; rituximab: 0.07 (0.01, 0.12) mm2, p = 0.019; azathioprine: 0.14 (0.02, 0.26) mm2, p = 0.023]. However, we detected no significant differences in annual changes in mGCC, pRNFL, TMV, and cup area between patients with tocilizumab, rituximab, and azathioprine in NMOSDON+ eyes. NMOSDON- eyes did not display mGCC or pRNFL thinning in patients treated with tocilizumab and rituximab. Intriguingly, we observed significant thinning of mGCC in patients treated with azathioprine compared with tocilizumab [-0.84 (-1.50, -0.18) µm vs. -0.19 (-0.87, 0.48) µm, p = 0.012] and rituximab [-0.84 (-1.50, -0.18) µm vs. -0.07 (-1.25, -2.51) µm, p = 0.015] in NMOSDON- eyes. Conclusions: This study demonstrated that retinal ganglion cell loss is independent of ON attacks in NMOSD. Tocilizumab and rituximab may delay mGCC thinning in NMOSDON- eyes compared with azathioprine.

The occurrence of myelin oligodendrocyte glycoprotein antibodies in aquaporin-4-antibody seronegative Neuromyelitis Optica Spectrum Disorder: A systematic review and meta-analysis.

BACKGROUND: Despite inclusion in neuromyelitis optica spectrum disorders (NMOSD), myelin oligodendrocyte glycoprotein antibody (MOG-Ab)-associated diseases are increasingly recognized as an independent disease entity. In this study, we conducted a systematic review and meta-analysis to comprehensively update the rate of occurrence of MOG-Ab in Aquaporin4 (AQP4)-antibody seronegative NMOSD. METHODS: We searched PubMed, EMBASE, and Cochrane databases for studies reporting the rates of patients with MOG-Ab in NMOSD. Fixed or random-effects models were used to pool results across studies. RESULTS: Fourteen studies met the inclusion criteria. Overall, MOG-Abs positive patients comprised 9.3% of all NMO/NMOSD (95% confidence interval [CI] 7.9%-10.8%, I2 = 13.1%), 32.5% of all AQP4-Ab seronegative NMO/NMOSD (95% CI 25.7%-39.3%, I2 = 45.8%), and 41.6% of AQP4-Ab seronegative NMOSD cases diagnosed by IPND 2015 criteria (95% CI 35.1%-48.2%, I2 = 0.0%). The pooled prevalence of MOG-Ab was 31.0% among Asian AQP4-Ab seronegative NMO/NMOSD patients (95% CI 22.1%-39.9% I2=54.1%) and 34.3% in European seronegative NMO/NMOSD (95% CI 21.9%-46.7%, I2 = 51.9%). CONCLUSIONS: This study shows that MOG-Abs represent a substantial proportion of AQP4-Ab seronegative NMOSD patients despite different underlying mechanisms, clinical manifestations, and treatment response, suggesting MOG-Ab screening in AQP4-Ab seronegative NMOSD patients can facilitate accurate diagnoses and treatments.

Asian and African/Caribbean AQP4-NMOSD patient outcomes according to self-identified race and place of residence.

BACKGROUND: Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune astrocytopathy characterized by aquaporin-4 antibodies, whose prognosis is influenced by onset age, race, environmental exposures and immunosuppression. Distinguishing the contribution of environment from genetics is challenging. We aimed to compare neuromyelitis optica spectrum disorder (NMOSD) patient outcomes according to self-identified racial group and place of residence. METHODS: This retrospective analysis of prospectively collected data included non-white anti-aquaporin-4 antibody positive NMOSD patients under follow-up from 15 centers [United Kingdom, France, Germany, Denmark, Martinique, United States of America, Japan, South Korea, Singapore, Thailand, China (including Hong Kong) and India]. Racial groups were designated: African/Caribbean; South Asian; East Asian (including Southeast Asia). Patients from these racial groups residing outside Africa/Caribbean or Asia were compared with those living in the Caribbean or the Asian areas. Kaplan-Meier survival curves and Cox models were generated using time to sustained Expanded Disability Status Scale≥6.0 or death; time to sustained Kurtzke Visual Function Score≥3.0 or a composite endpoint of all three. RESULTS: Among 821 patients, African/Caribbean patients (n = 206) had the shortest time to immunosuppression and higher visual disability at onset. South Asian patients (n = 65) were younger, had lower visual disability at onset and higher mortality rate. East Asians (n = 550) had the lowest relapse rate and lowest accrued motor disability. Survival analysis of African/Caribbean outside Africa/Caribbean vs those in the Caribbean showed a significant difference in the composite endpoint (p = 0.024,log-rank test), not apparently related to treatment differences. No significant differences between native and those residing outside Asia were found for other racial groups. CONCLUSION: This NMOSD study reports the effects of place of residence on the outcomes in different races. Place of residence may not be a significant driver of disability among Asian patients, while it may influence African/Caribbean patient outcomes. Validating these findings could help distinguish between genetic causes and potentially modifiable environmental factors.

Cortical Thinning and Ventricle Enlargement in Neuromyelitis Optica Spectrum Disorders.

Background: In neuromyelitis optica spectrum disorders (NMOSDs), inflammation is not the sole driver of accumulation of disability; neurodegeneration is another important pathological process. We aim to explore different patterns of cortical atrophy and ventricular enlargement in NMOSD. Methods: We retrospectively analyzed a cohort of 230 subjects, comprising 55 healthy controls (HCs), 85 multiple sclerosis (MS), and 90 NMOSD patients from Tianjin Medical University General Hospital and Beijing Tiantan Hospital. Different compartments of the brain (total gray, cortex, subcortex gray, and ventricle volume) were evaluated with the FreeSurfer. Multiple linear regressions were adopted to explore associations between cortex volume and predict factors. Results: Compared with HCs, NMOSD, and MS displayed an enlarged lateral and third ventricle (p < 0.001), whereas expansion of the fourth ventricle was observed in MS rather than NMOSD (p = 0.321). MS and NMOSD patients exhibited cortical thinning in comparison with HCs. However, pronounced cortical atrophy were only significant in pre-cuneus, parahippocampal, and lateral occipital lobe between MS and NMOSD. Patients with NMOSD had decreased local gyrification index in orbitofrontal and pre-cuneus lobe, and reduced pial surface area. Linear regression analysis revealed cortex volume were predicated by advanced age (standardized ß = -0.404, p = 0.001) as well as prolonged disease history (standardized ß = -0.311, p = 0.006). Conclusion: NMOSD exhibited global cortex atrophy with enlarged lateral and third ventricles. Moreover, cortex volume is associated with age and disease duration.

Intravenous immunoglobulin for acute attacks in neuromyelitis optica spectrum disorders (NMOSD).

BACKGROUND: During acute attacks of neuromyelitis optica spectrum disorder (NMOSD), intravenous immunoglobulin (IVIG) maybe useful building on experience treating autoimmune disorders. METHODS: We conducted a retrospective study of several treatment modes for NMOSD attacks at Beijing Tiantan Hospital and Tianjin Medical University General Hospital. Clinical outcomes were defined as the short-term remission status. The good (GR), moderate (MR) or poor remission (PR) was respectively defined to triple-grade based on percentage change of initial and follow-up Expanded Disability Status Scale (EDSS) scores. RESULTS: A total of 243 attacks was analyzed in 198 patients from 2014 to 2019. Treatment groups included 153 attacks given high-dose intravenous steroids (HD-S), 14 given IVIG, 69 episodes of IVIG plus HD-S and 7 treated with plasma exchange. The proportion of patients with better outcomes were significantly lower in IVIG alone group than HD-S alone group (p = 0.004). However, sequential treatments for IVIG and HD-S yielded a higher likelihood of clinical improvement in severe attacks with EDSS ≥ 6.5 (OR = 5.85, p = 0.007). CONCLUSION: These results did not support IVIG-alone therapy as a first-line option for acute NMOSD. However, adding HD-S to IVIG therapy was superior to HD-S alone for patients with high-onset EDSS.

Risk of COVID-19 infection in MS and neuromyelitis optica spectrum disorders.

OBJECTIVE: Disease-modifying drugs (DMDs) may alter the immune status and thus increase the susceptibility to coronavirus disease 2019 (COVID-19) in patients with MS or neuromyelitis optica spectrum disorders (NMOSD). However, evidence supporting this notion is currently lacking. In this study, we conducted a survey on the risk of COVID-19 in patients with MS and NMOSD. METHODS: The survey was conducted through the Chinese Medical Network for Neuroinflammation. Patients in 10 MS centers from 8 cities including Wuhan were included. Information about MS and NMOSD disease duration and the usage of DMDs were collected. Data of suspected cases of COVID-19 were obtained from hospital visits, questionnaires, and patient self-reporting. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was confirmed through clinical evaluation by a panel of experts in conjunction with chest CT and viral RNA detection. RESULTS: Eight hundred eighty-two of 1,804 (48.89%) patients with MS and 2,129 of 3,060 (69.58%) patients with NMOSD were receiving DMDs. There were no alterations in the patients' DMD regimen during January 15, 2020, to March 15, 2020, the 3-month period. None of the patients with MS treated with DMDs had COVID-19. However, 2 patients with relapsing NMOSD were diagnosed with COVID-19-related pneumonia. After treatment, both patients recovered from pneumonia and neither patient experienced new attacks due to predisposing SARS-CoV-2 infection in the following 2 months. CONCLUSIONS: No increased risk of COVID-19 infection was observed in patients with MS or NMOSD, irrespective of whether these patients received DMDs. A battery of stringent preventive measures adopted by neurologists to reduce COVID-19 infection in these patients may have contributed to low risk of COVID-19 infection.

Inhibition of activator protein 1 attenuates neuroinflammation and brain injury after experimental intracerebral hemorrhage.

AIMS: Intracerebral hemorrhage (ICH) is a devastating type of stroke without specific treatment. Activator protein 1 (AP-1), as a gene regulator, initiates cytokine expression in response to environmental stimuli. In this study, we investigated the relationship between AP-1 and neuroinflammation-associated brain injury triggered by ICH. METHODS: Intracerebral hemorrhage mice were developed by autologous blood or collagenase infusion. We measured the dynamics of AP-1 in mouse brain tissues during neuroinflammation formation after ICH. The effects of the AP-1 inhibitor SR11302 on brain injury and neuroinflammation as well as the underlying mechanisms were investigated in vivo and in vitro. RESULTS: AP-1 was significantly upregulated in mouse brain tissue as early as 6 hours after ICH, accompanied by elevations in proinflammatory factors, including interleukin (IL)-6, IL-1ß, and tumor necrosis factor (TNF)-α. Inhibition of AP-1 using SR11302 reduced neurodeficits and brain edema at day 3 after ICH. SR11302 ablated microglial IL-6 and TNF-α production and brain-infiltrating leukocytes in ICH mice. In addition, SR11302 treatment diminished thrombin-induced production of IL-6 and TNF-α in cultured microglia. CONCLUSIONS: Inhibition of AP-1 curbs neuroinflammation and reduces brain injury following ICH.

Comparison of brain and spinal cord magnetic resonance imaging features in neuromyelitis optica spectrum disorders patients with or without aquaporin-4 antibody.

BACKGROUND: The spinal cord and brain measurements are rarely investigated in neuromyelitis optica (NMO) patients with and without antibodies to aquaporin-4 (AQP4), directly compared to multiple sclerosis (MS) patients. OBJECTIVES: To investigate magnetic resonance imaging (MRI) features of both brain and spinal cord in NMO patients with and without antibodies to AQP4, compared with MS patients and healthy controls (HC). METHODS: We recruited 55 NMO including 30 AQP4 (+) and 25 AQP4 (-), 25 MS and 25 HC. Brain and spinal cord MRIs were obtained for each participant. Brain lesions (BL), whole brain and deep grey matter volumes (DGMV), white matter diffusion metrics and spinal cord lesions were measured and compared among groups. RESULTS: The incidence of BL was lower in the AQP4 (+) group than in the AQP4 (-) and MS groups (p<0.05). In the AQP4 (+) group, there was a lower incidence of infratentorial lesions (ITL) and higher spinal cord lesions length than in the MS group (p<0.05). The thalamic and hippocampal volumes were smaller in the AQP4 (-) group and MS group than in the HC group (p<0.05). CONCLUSIONS: The NMO patients with AQP4 (-) showed higher prevalence of BL, ITL, and similar spinal cord lesion length, compared to AQP4 (+), and demonstrated deep grey matter atrophy, suggesting an intermediate phenotype between that of typical MS and NMO.

Structural MRI substrates of cognitive impairment in neuromyelitis optica.

OBJECTIVE: To identify the clinical and structural MRI markers for predicting cognitive impairment (CI) in patients with neuromyelitis optica (NMO). METHODS: Fifty-four patients with NMO and 27 healthy controls underwent extensive neuropsychological testing and multimodal 3.0T MRI. The patient group was classified as CI or cognitively preserved (CP), using a criterion of ≤1.5 SD on at least 2 cognitive domains. MRI measurements included white matter (WM) lesion volume, gray matter (GM), WM, and deep GM (DGM) volume, cortical thickness, and the severity and extent of WM tract diffusion metric alterations based on fractional anisotropy and mean, axial, and radial diffusivity. Groups were compared using a multivariate general linear model, and clinical and MRI measurements were related to average cognition z scores by partial correlations and a stepwise linear regression model. RESULTS: Twenty-six patients with NMO (48.2%) were classified as CI and showed WM tract diffusion abnormalities, particularly increased radial diffusivity, and GM especially DGM atrophy compared with healthy controls. Patients classified as CP also showed alterations of WM tract diffusion but without significant GM atrophy. Compared with the CP group, patients with CI demonstrated a lower level of education and decreased hippocampal volume. In the whole patient group, average cognition z scores were best predicted by the level of education and hippocampal volume (R(2) = 0.46, p < 0.001). CONCLUSION: In patients with NMO, WM tract integrity disruption was identified in both CP and CI groups. GM atrophy, particularly in the DGM, was only found in the CI group. Hippocampal volume is the main MRI predictor of cognition in NMO.