MOG-IgG in NMO and related disorders: a multicenter study of 50 patients. Part 2: Epidemiology, clinical presentation, radiological and laboratory features, treatment responses, and long-term outcome

Progression independent of relapses in aquaporin4-IgG-seropositive neuromyelitis optica spectrum disorder, myelin oligodendrocyte glycoprotein antibody-associated disease, and multiple sclerosis

OBJECTIVES

To determine whether progression independent of relapse activity (PIRA) is present in Aquaporin4-IgG-seropositive neuromyelitis optica spectrum disorder (AQP4+NMOSD), Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and relapsing remitting Multiple sclerosis (RRMS).

METHODS

We retrospectively studied the change in EDSS, confirmed disability worsening (CDW) (i.e., PIRA), and new MRI lesions in AQP4+NMOSD, and MOGAD and MS patients. Linear mixed-effect regression model was used to compare the longitudinal changes in EDSS, and Cox regression was used to compare changes in MRI.

RESULTS

The estimated mean ΔEDSS in the AQP4+NMOSD and matched MS group were +0.06 (95%CI: -0.40, +0.52, p = 0.76), and +0.02 (95%CI: -0.05, +0.08, p = 0.6) respectively. The same estimate was -0.08 (95%CI: -0.18, +0.02, p = 0.12) in MOGAD and +0.05 (95%CI: -0.05, +0.15, p = 0.35) in matched MS group. Comparing groups for the presence of CDW (i.e., PIRA) showed that PIRA is more associated with MS compared to AQP4+NMOSD (p = 0.02) and MOGAD (p<0.001). Compared to their matched MS groups, the annualized rate of PIRA was significantly lower in AQP4 (0.08 vs 0.44; p<0.0001), and MOG groups (0.04 vs 0.13; p<0.0001). New T2 or enhancing lesions on brain MRI were higher in MS compared to AQP4+NMOSD and MOGAD patients.

CONCLUSION

Relapse-independent changes in the EDSS, CDW, and MRI activity are not common in AQP4+NMOSD and MOGAD, especially when compared with MS. Since our patients were on relapse prevention therapies at the time of EDSS measurements, our study supports the importance of preventing relapses in AQP4+NMOSD and MOGAD and suggests different pathologic mechanisms of relapse-free neurological damage between MS and AQP4+NMOSD/MOGAD.

SARS-CoV-2 Parainfectious Optic Neuropathy: 3 Case Reports and a Review of the Literature

BACKGROUND

Parainfectious optic neuritis is an inflammatory reaction that occurs shortly after an infection without direct invasion by a pathogen. The clinical profile depends on the infectious organism. Cases of SARS-CoV-2 parainfectious optic neuritis have been reported in the literature, but there are no reviews that have applied strict inclusion criteria to more definitively establish the clinical profile associated with SARS-CoV-2.

METHODS

We present 3 new cases of SARS-CoV-2 parainfectious optic neuritis. We also review the literature for definite cases by selecting only those with unambiguous clinical features and MRI findings of optic neuritis, positive SARS-CoV-2 polymerase chain reaction or serology, and the absence of myelin oligodendrocyte-glycoprotein or aquaporin-4 antibodies or other diseases associated with optic neuritis.

RESULTS

We report 2 cases of monophasic, unilateral SARS-CoV-2 parainfectious optic neuritis with optic disc edema and nadir visual acuities of finger counting. We report 1 case of mild SARS-CoV-2 parainfectious optic neuritis that featured cotton wool spots, peripapillary wrinkles and hemorrhages, and recurrence after an initial steroid taper. We identified 6 cases of unambiguous SARS-CoV-2 parainfectious optic neuritis from the literature. Combining our case series with the case reports in the literature, the average age was 42.8 years, 3/9 had bilateral disease, 6/8 had optic disc edema, 8/9 had nadir visual acuity of finger counting or worse, and all recovered visual acuity to 20/40 or better after therapy with steroids.

CONCLUSIONS

SARS-CoV-2 parainfectious optic neuritis has a clinical profile that is atypical for idiopathic optic neuritis but fairly typical of parainfectious forms of optic neuritis with a severely reduced nadir visual acuity, high likelihood of bilaterality, high incidence of optic disc edema, and prompt and significant response to corticosteroids. Further study with long-term follow-up and epidemiologic investigation will be needed to further characterize this clinical entity.

NF-κB and STAT3 activation in CD4 T cells in pediatric MOG antibody-associated disease

In this study, we examined CD4 T cell activation using various stimuli in pediatric MOGAD patients (n = 4, untreated remission samples) and healthy controls (n = 5), to understand how both antigen-specific and bystander mechanisms contribute to CD4 T cell activation in MOGAD. TNFα, IL6, and MOG peptide pool were found to activate NF-κB or STAT3 pathways by measuring the expression of regulators (A20, IκBα) and phosphorylated subunits (phospho-p65 and phospho-STAT3) using immunolabeling. Prednisolone reversed activation of both NF-κB and STAT3 and increased the expression of A20 and IκBα. TNFR blocking partially reversed NF-κB activation in certain CD4 T cell subsets, but did not effect STAT3 activation. We observed that activation of NF-κB and STAT3 in response to various stimuli behaves mostly same in MOGAD (remission) and HC. IL6 stimulation resulted in higher STAT3 phosphorylation in MOGAD patients at 75 min, specifically in central and effector memory CD4 T cells (with unadjusted p-values). These findings suggest the potential therapeutic targeting of NF-κB and STAT3 pathways in MOGAD. Further investigation is needed to validate the significance of extended STAT3 phosphorylation and its correlation with IL6 receptor blocker treatment response.

Neuromyelitis Optica spectrum disorders in Argentina: A hospital-based study

BACKGROUND

Neuromyelitis Optica spectrum disorder (NMOSD) is an antibody-mediated autoimmune disease of the CNS, which especially affects the optic nerves and spinal cord. There is little known in Latin America (LATAM) about NMOSD, and few reports have been published in the literature so far. We aimed to describe an NMOSD study in a single center from Argentina.

METHODS

A retrospective cross sectional study was carried out in a single reference center in the city of Buenos Aires, Argentina. Data were collected from January 2000 through December 2021 using medical records from patients attending Ramos Mejia Hospital in Buenos Aires, Argentina. Here we describe the clinical, laboratory, MRI, disability course, and treatment of 92 NMOSD patients.

RESULTS

Mean age at the onset of symptoms was 31 years (range 2-68) with a female/male ratio of 4.8:1. 71.7 % had an early onset before the age of 50 years old, 8.7 % had a late onset of the disease and 19.6 % had an onset at pediatric age. The first symptom of NMOSD was optic neuritis in 47.8 % of the patients, followed by transverse myelitis, 33.7 % and area postrema syndrome, 5.4 %. 96.7 % of patients relapsed at least once during the follow-up period. The mean of the expanded disability status scale (EDSS) was 4.0 (range 2-8). 34,8 % had one or more associated autoimmune diseases. 78,6 % had a positive result for AQP4-IgG. The ratio of male to female was 1:8.4 vs.1:1.2 in the seropositive group vs. the seronegative. CSF results showed OCB type 2 in 6.3 %. The brain MRI did not show brain lesions in 71,7 % of the patients. 17 % presented spinal cord lesions with less than 3 vertebral segments. All patients received treatment with immunosuppressive drugs. Rituximab and azathioprine were the most used.

CONCLUSIONS

This is the largest hospital-based study in an Argentina cross-sectional study of patients with NMOSD. Recurrent disease, early age at onset, female prevalence in AQP4-IgG+ patients, and the difficulty to assess new treatments, are the highlight features in our study of patients. Further Argentinian and LATAM studies will provide more information.

Clinical spectrum of myelin oligodendrocyte glycoprotein antibody-associated disease in Brazil: a single-center experience

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.

Clinical characteristics and long-term follow-up outcomes of myelin oligodendrocyte glycoprotein antibody-associated disease in Han Chinese participants

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an immune-mediated inflammatory demyelinating disease of the central nervous system. This study aimed to delineate the clinical manifestations, imaging features, and long-term outcomes in Chinese patients with MOGAD and analyze the recurrence-associated factors. The phenotypic and neuroimaging characteristics of 15 Han Chinese patients with MOGAD were retrospectively analyzed. Demyelinating attacks, MOG antibodies in the cerebrospinal fluid/serum, response to immunotherapy, follow-up outcomes, and recurrence-associated factors were recorded. The median age at disease onset was 34 years (range, 4-65 years). The most common initial presentations included vision loss (10/15, 66.7%) and seizures (5/15, 33.3%). Serum MOG-Ab titers in 14/15 cases were higher than those in the cerebrospinal fluid and were detected in 3/6 relapsed patients. Brain magnetic resonance imaging during acute attacks showed lesions in 10/15 patients (66.7%), mostly in the cortex/subcortical white matter (5/15, 33.3%). Recurrence occurred in 6/15 patients (40.0%); in 4 patients, recurrence occurred shortly after immunotherapy discontinuation. Residual neurological deficits were present in 5/15 patients (33.3%), including visual impairment, incapacitation, cognitive impairment, and speech reduction. Optic neuritis was the most common clinical manifestation of MOGAD. magnetic resonance imaging findings were heterogeneous and the cerebral cortex/subcortical white matter was the most susceptible brain region. Although patients in the acute phase responded well to methylprednisolone pulse therapy, the long-term recurrence rate was high. Consistently detected serum MOG antibodies and inappropriate maintenance immunotherapy may be associated with recurrence, and residual neurological deficits should not be ignored.

Perplexing Initial Presentations of MOGAD in Two Children: Intracranial Hypertension and New-Onset Seizure

We report two distinct challenging initial presentations of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Case 1 describes a 12-year-old boy who developed headaches refractory to pain medication followed by cranial neuropathies and intracranial hypertension, confirmed by lumbar puncture with an opening pressure >36 cm H2O. Case 2 describes a 3-year-old boy who developed new-onset seizures refractory to antiseizure medications, a presentation of FLAIR-hyperintense lesions in MOG-antibody associated encephalitis with seizures (FLAMES). On repeat magnetic resonance imaging, both patients were found to have cortical T2 hyperintensities, leptomeningeal contrast enhancement, and bilateral optic nerve enhancement. In the cerebrospinal fluid, both patients had CSF pleocytosis with neutrophilic predominance. The patients were treated with intravenous immunoglobulins, plasma exchange, and high-dose corticosteroids. The first patient achieved disease remission, whereas the second patient required the addition of rituximab for management of seizures. The two cases highlight the pleomorphic clinical phenotypes of MOGAD.

An update on optic neuritis

Optic neuritis (ON) is the most common cause of subacute optic neuropathy in young adults. Although most cases of optic neuritis (ON) are classified as typical, meaning idiopathic or associated with multiple sclerosis, there is a growing understanding of atypical forms of optic neuritis such as antibody mediated aquaporin-4 (AQP4)-IgG neuromyelitis optica spectrum disorder (NMOSD) and the recently described entity, myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD). Differentiating typical ON from atypical ON is important because they have different prognoses and treatments. Findings of atypical ON, including severe vision loss with poor recovery with steroids or steroid dependence, prominent optic disc edema, bilateral vision loss, and childhood or late adult onset, should prompt serologic testing for AQP4-IgG and MOG-IgG. Although the traditional division of typical and atypical ON can be helpful, it should be noted that there can be severe presentations of otherwise typical ON and mild presentations of atypical ON that blur these traditional lines. Rare causes of autoimmune optic neuropathies, such as glial fibrillary acidic protein (GFAP) and collapsin response-mediator protein 5 (CRMP5) autoimmunity also should be considered in patients with bilateral painless optic neuropathy associated with optic disc edema, especially if there are other accompanying suggestive neurologic symptoms/signs. Typical ON usually recovers well without treatment, though recovery may be expedited by steroids. Atypical ON is usually treated with intravenous steroids, and some forms, such as NMOSD, often require plasma exchange for acute attacks and long-term immunosuppressive therapy to prevent relapses. Since treatment is tailored to the cause of the ON, elucidating the etiology of the ON is of the utmost importance.

Clinical feature and disease outcome in patients with myelin oligodendrocyte glycoprotein antibody-associated disorder: a Chinese study

BACKGROUND

To identify factors associated with relapse risk and disability in myelin oligodendrocyte glycoprotein antibody-associated disorder (MOGAD).

METHOD

Between 2016 and 2021, 186 patients with MOGAD were included in the study. Factors associated with a relapsing course, annualised relapse rate (ARR), recurrent relapses under different maintenance treatments and unfavourable disability outcome were analysed.

RESULTS

MOGAD affects women (53.8%) slightly more often than men. After a median disease duration of 51.0 months, 60.2% (112/186) relapsed, with an overall ARR of 0.5. The ARR (0.6 vs 0.4, p=0.049), median Expanded Disability Status Scale (EDSS) score (1 (range 0-9.5) vs 1 (range 0-3.5), p=0.005) and Visual Functional System Score (VFSS) (0 (range 0-6) vs 0 (range 0-3), p=0.023) at last visit were higher in adults than in children, and time to first relapse was shorter in adults than in children (4.1 (range 1.0-111.0) vs 12.2 (range 1.3-266.8) months, p=0.001). Myelin oligodendrocyte glycoprotein antibody (MOG-ab) persistence over 1 year was associated with a relapsing course (OR 7.41, 95% CI 2.46 to 22.33, p=0.000), while timely maintenance therapy was associated with a lower ARR (p=0.008). More than four attacks (OR 4.86, 95% CI 1.65 to 14.28, p=0.004) and poor recovery from the first attack (OR 75.28, 95% CI 14.45 to 392.05, p=0.000) were associated with an unfavourable outcome (EDSS score ≥2 including VFSS ≥2).

CONCLUSIONS

The results underscored the importance of timely maintenance treatment to prevent further relapses, especially in adult patients with persistently positive MOG-ab and unsatisfactory recovery from the onset attack.

Timing and Predictors of T2-Lesion Resolution in Patients With Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease

OBJECTIVES

To determine the timing and predictors of T2-lesion resolution in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD).

METHODS

This retrospective observational study using standard-of-care data had inclusion criteria of MOGAD diagnosis, ≥2 MRIs 12 months apart, and ≥1 brain/spinal cord T2-lesion. The median (interquartile range [IQR]) number of MRIs (82% at disease onset) per-patient were: brain, 5 (2-8); spine, 4 (2-8). Predictors of T2-lesion resolution were assessed with age- and sex-adjusted generalized estimating equations and stratified by T2-lesion size (small <1 cm; large ≥1 cm).

RESULTS

We studied 583 T2-lesions (brain, 512 [88%]; spinal cord, 71 [12%]) from 55 patients. At last MRI (median follow-up 54 months [IQR 7-74]) 455 T2-lesions (78%) resolved. The median (IQR) time to resolution was 3 months (1.4-7.0). Small T2-lesions resolved more frequently and faster than large T2-lesions. Acute T1-hypointensity decreased the likelihood (odds ratio [95% CI]) of T2-lesion resolution independent of size (small: 0.23 [0.09-0.60], p = 0.002; large: 0.30 [0.16-0.55], p < 0.001), whereas acute steroids favored resolution of large T2-lesions (1.75 [1.01-3.03], p = 0.046). Notably, 32/55 (58%) T2-lesions resolved without treatment.

DISCUSSION

The high frequency of spontaneous T2-lesion resolution suggests that this represents MOGAD's natural history. The speed of T2-lesion resolution and influence of size, corticosteroids, and T1-hypointensity on this phenomenon gives insight into MOGAD pathogenesis.

Epidemiology of myelin oligodendrocyte glycoprotein antibody-associated disease: a review of prevalence and incidence worldwide

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an inflammatory demyelinating disease of the central nervous system (CNS) with the presence of conformation-sensitive antibodies against MOG. The spectrum of MOGAD includes monophasic/relapsing optic neuritis, myelitis, neuromyelitis optica spectrum disorder (NMOSD) phenotype without aquaporin 4 (AQP4) antibodies, acute/multiphasic demyelinating encephalomyelitis (ADEM/MDEM)-like presentation, and brainstem and cerebral cortical encephalitis. There is no apparent female preponderance in MOGAD, and MOGAD can onset in all age groups (age at onset is approximately 30 years on average, and approximately 30% of cases are in the pediatric age group). While prevalence and incidence data have been available for AQP4+ NMOSD globally, such data are only beginning to accumulate for MOGAD. We reviewed the currently available data from population-based MOGAD studies conducted around the world: three studies in Europe, three in Asia, and one joint study in the Americas. The prevalence of MOGAD is approximately 1.3-2.5/100,000, and the annual incidence is approximately 3.4-4.8 per million. Among White people, the prevalence of MOGAD appears to be slightly higher than that of AQP4+ NMOSD. No obvious latitude gradient was observed in the Japanese nationwide survey. The data available so far showed no obvious racial preponderance or strong HLA associations in MOGAD. However, precedent infection was reported in approximately 20-40% of MOGAD cases, and this is worthy of further investigation. Co-existing autoimmune disorders are less common in MOGAD than in AQP4+ NMOSD, but NMDAR antibodies may occasionally be positive in patients with MOGAD. More population-based studies in different populations and regions are useful to further inform the epidemiology of this disease.

Basic CSF parameters and MRZ reaction help in differentiating MOG antibody-associated autoimmune disease versus multiple sclerosis

Background

Myelin oligodendrocyte glycoprotein antibody-associated autoimmune disease (MOGAD) is a rare monophasic or relapsing inflammatory demyelinating disease of the central nervous system (CNS) and can mimic multiple sclerosis (MS). The variable availability of live cell-based MOG-antibody assays and difficulties in interpreting low-positive antibody titers can complicate diagnosis. Literature on cerebrospinal fluid (CSF) profiles in MOGAD versus MS, one of the most common differential diagnoses, is scarce. We here analyzed the value of basic CSF parameters to i) distinguish different clinical MOGAD manifestations and ii) differentiate MOGAD from MS.

Methods

This is retrospective, single-center analysis of clinical and laboratory data of 30 adult MOGAD patients and 189 adult patients with relapsing-remitting multiple sclerosis. Basic CSF parameters included CSF white cell count (WCC) and differentiation, CSF/serum albumin ratio (QAlb), intrathecal production of immunoglobulins, CSF-restricted oligoclonal bands (OCB) and MRZ reaction, defined as intrathecal production of IgG reactive against at least 2 of the 3 viruses measles (M), rubella (R) and varicella zoster virus (Z).

Results

MOGAD patients with myelitis were more likely to have a pleocytosis, a QAlb elevation and a higher WCC than those with optic neuritis, and, after review and combined analysis of our and published cases, they also showed a higher frequency of intrathecal IgM synthesis. Compared to MS, MOGAD patients had significantly more frequently neutrophils in CSF and WCC>30/µl, QAlb>10×10-3, as well as higher mean QAlb values, but significantly less frequently CSF plasma cells and CSF-restricted OCB. A positive MRZ reaction was present in 35.4% of MS patients but absent in all MOGAD patients. Despite these associations, the only CSF parameters with relevant positive likelihood ratios (PLR) indicating MOGAD were QAlb>10×10-3 (PLR 12.60) and absence of CSF-restricted OCB (PLR 14.32), whereas the only relevant negative likelihood ratio (NLR) was absence of positive MRZ reaction (NLR 0.00).

Conclusion

Basic CSF parameters vary considerably in different clinical phenotypes of MOGAD, but QAlb>10×10-3 and absence of CSF-restricted OCB are highly useful to differentiate MOGAD from MS. A positive MRZ reaction is confirmed as the strongest CSF rule-out parameter in MOGAD and could be useful to complement the recently proposed diagnostic criteria.

Role of serostatus in pediatric neuromyelitis optica spectrum disorders: A nationwide multicentric study

BACKGROUND

Neuromyelitis optica spectrum disorders (NMOSD) are immune-mediated inflammatory disorders of the central nervous system (CNS) mostly presenting as optic neuritis and acute myelitis. NMOSD can be associated with seropositivity for aquaporin 4 antibody (AQP4 IgG), myelin oligodendrocyte glycoprotein antibody (MOG IgG), or can be seronegative for both. In this study, we retrospectively examined our seropositive and seronegative pediatric NMOSD patients.

METHOD

Data were collected from all participating centres nationwide. Patients diagnosed with NMOSD were divided into three subgroups according to serology: AQP4 IgG NMOSD, MOG IgG NMOSD, and double seronegative (DN) NMOSD. Patients with at least six months of follow-up were compared statistically.

RESULTS

The study included 45 patients, 29 female and 16 male (ratio:1.8), mean age 15.16 ± 4.93 (range 5.5-27) years. Age at onset, clinical manifestations, and cerebrospinal fluid findings were similar between AQP4 IgG NMOSD (n = 17), MOG IgG NMOSD (n = 10), and DN NMOSD (n = 18) groups. A polyphasic course was more frequent in the AQP4 IgG and MOG IgG NMOSD groups than DN NMOSD (p = 0.007). The annualized relapse rate and rate of disability were similar between groups. Most common types of disability were related to optic pathway and spinal cord involvement. Rituximab in AQP4 IgG NMOSD, intravenous immunoglobulin in MOG IgG NMOSD, and azathioprine in DN NMOSD were usually preferred for maintenance treatment.

CONCLUSION

In our series with a considerable number of double seronegatives, the three major serological groups of NMOSD were indistinguishable based on clinical and laboratory findings at initial presentation. Their outcome is similar in terms of disability, but seropositive patients should be more closely followed-up for relapses.

Clinical risk factors for recurrence of myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a CNS demyelinating disease that targets myelin oligodendrocyte glycoprotein and recurs in approximately 50% of patients after the initial episode. Multiple relapses may have adverse consequences, but the factors influencing relapse are unclear. This study analyzed the clinical risk factors for relapse in patients with MOGAD.

METHODS

Twenty-four MOGAD patients diagnosed at the Department of Neurology, First Hospital of Shanxi Medical University from March 2018 to November 2020 were retrospectively analyzed in this study. The patients were divided into a monophasic course and a relapsing course according to their disease process. The patients' epidemiological characteristics, clinical symptoms, laboratory tests, imaging features, and regression were summarized. Comparisons were made between the monophasic and relapsing course to identify the possible factors associated with the clinical features and recurrence.

RESULTS

At a mean follow-up of 15 months (range: 8 to 24 months), seventeen of the 24 patients (70.8%) had monophasic disease, and 7 (29.2%) had relapsing disease. Among the 24 patients, 17 patients (70.9%) had low Myelin oligodendrocyte glycoprotein antibody (MOG-IgG) serum titers (<1:100), and 7 patients (29.1%) had high MOG-IgG serum titers (≥1:100). Compared to the monophasic course group, patients in the relapsing course group had higher serum antibody titers (71.4% vs. 11.7%, P = 0.035). Onset phenotypes included encephalitis (50%), myelitis (45.8%), and optic neuritis (45.8%), with 66.7% of patients starting with a single phenotype and 33.3% starting with two or more phenotypes. Optic neuritis was more common in the relapsing course group (85.7%) than the monophasic course group (29.4%) (P = 0.023). There was no significant difference between the two groups in the proportion of myelitis and encephalitis. A previous history or background of immunological disease was present in 33.3% of patients, with a significantly higher proportion in the relapsing course group than in the monophasic course group (71.4% vs. 17.6%, P = 0.021). Regarding ancillary examinations, the relapsing course group was more likely to have CSF leukocytes higher than 50/mm3 than the monophasic course group (60% vs. 0, P = 0.045), while there was no difference in the number and site distribution of the lesions on MRI.

CONCLUSIONS

Our study suggests that the most common clinical manifestations of MOGAD are diminished visual acuity, limb/facial numbness, and ocular/orbital pain. The onset phenotype consisting of optic neuritis, a history of immune disease, high antibody titers (≥1:100), and high cerebrospinal fluid leukocytes (above 50/mm3) suggests a high likelihood of MOGAD recurrence.

Do Early Relapses Predict the Risk of Long-Term Relapsing Disease in an Adult and Paediatric Cohort with MOGAD?

OBJECTIVE

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) can be monophasic or relapsing, with early relapse being a feature. However, the relevance of early relapse on longer-term relapse risk is unknown. Here, we investigate whether early relapses increase longer-term relapse risk in patients with MOGAD.

METHODS

A retrospective analysis of 289 adult- and pediatric-onset patients with MOGAD followed for at least 2 years in 6 specialized referral centers. "Early relapses" were defined as attacks within the first 12 months from onset, with "very early relapses" defined within 30 to 90 days from onset and "delayed early relapses" defined within 90 to 365 days. "Long-term relapses" were defined as relapses beyond 12 months. Cox regression modeling and Kaplan-Meier survival analysis were used to estimate the long-term relapse risk and rate.

RESULTS

Sixty-seven patients (23.2%) had early relapses with a median number of 1 event. Univariate analysis revealed an elevated risk for long-term relapses if any "early relapses" were present (hazard ratio [HR] = 2.11, p < 0.001), whether occurring during the first 3 months (HR = 2.70, p < 0.001) or the remaining 9 months (HR = 1.88, p = 0.001), with similar results yielded in the multivariate analysis. In children with onset below aged 12 years, only delayed early relapses were associated with an increased risk of long-term relapses (HR = 2.64, p = 0.026).

INTERPRETATION

The presence of very early relapses and delayed early relapses within 12 months of onset in patients with MOGAD increases the risk of long-term relapsing disease, whereas a relapse within 90 days appears not to indicate a chronic inflammatory process in young pediatric-onset disease. ANN NEUROL 2023;94:508-517.

Clinical features of MOGAD with brainstem involvement in the initial attack versus NMOSD and MS

OBJECTIVE

To assess the characteristics of Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disorder (MOGAD) with brainstem involvement in the first event (BSIFE) and make comparisons with aquaporin-4-IgG seropositive neuromyelitis optica spectrum disorder (AQP4-IgG-NMOSD) and multiple sclerosis (MS).

METHODS

From 2017 to 2022, this study identified MOG-IgG-positive patients with brainstem or both brainstem and cerebellum lesions in the first episode. As a comparison group, AQP4-IgG-NMOSD (n = 30) and MS (n = 30) patients with BSIFE were enroled.

RESULTS

Thirty-five patients (35/146, 24.0%) were the BSIFE of MOGAD. Isolated brainstem episodes occurred in 9 of the 35 (25.7%) MOGAD patients, which was similar to MS (7/30, 23.3%) but was lower than AQP4-IgG-NMOSD (17/30, 56.7%, P = 0.011). Pons (21/35, 60.0%), medulla oblongata (20/35, 57.1%) and middle cerebellar peduncle (MCP, 19/35, 54.3%) were the most frequently affected areas. Intractable nausea (n = 7), vomiting (n = 8) and hiccups (n = 2) happened in MOGAD patients, but EDSS of MOGAD was lower than AQP4-IgG-NMOSD (P = 0.001) at the last follow-up. MOGAD patients with or without BSIFE did not significantly differ in terms of the ARR (P = 0.102), mRS (P = 0.823), or EDSS (P = 0.598) at the most recent follow-up. Specific oligoclonal bands appeared in MOGAD (13/33, 39.4%) and AQP4-IgG-NMOSD (7/24, 29.2%) in addition to MS (20/30, 66.7%). Fourteen MOGAD patients (40.0%) experienced relapse in this study. When the brainstem was involved in the first attack, there was an increased likelihood of a second attack occurring at the same location (OR=12.22, 95%CI 2.79 to 53.59, P = 0.001). If the first and second events were both in the brainstem, the third event was likely to occur at the same location (OR=66.00, 95%CI 3.47 to 1254.57, P = 0.005). Four patients experienced relapses after the MOG-IgG turned negative.

CONCLUSION

BSIFE occurred in 24.0% of MOGAD. Pons, medulla oblongata and MCP were the most frequently involved regions. Intractable nausea, vomiting and hiccups occurred in MOGAD and AQP4-IgG-NMOSD, but not MS. The prognosis of MOGAD was better than AQP4-IgG-NMOSD. In contrast to MS, BSIFE may not indicate a worse prognosis for MOGAD. When patients with BSIFE, MOGAD tent to reoccur in the brainstem. Four of the 14 recurring MOGAD patients relapsed after the MOG-IgG test turned negative.

[A case of anti-myelin oligodendrocyte glycoprotein antibody-positive multiphasic disseminated encephalomyelitis showing significant recovery after immunoadsorption plasmapheresis]

The patient is an 18-year-old female. She had a history of acute disseminated encephalomyelitis at the age of 6 and 7. She visited our hospital due to acute disturbance of consciousness, quadriplegia, and numbness of left upper and lower extremities. Brain MRI showed multiple DWI/FLAIR high-signal lesions in the bilateral cerebral hemispheres, cerebellum, and brainstem. Qualitative test indicated that serum anti-MOG antibodies was positive, and she was diagnosed with anti-MOG antibody-positive polyphasic disseminated encephalomyelitis. Intravenous mPSL pulse therapy was performed twice, but the symptoms worsened. As a second line treatment, plasma exchange was started. However, she developed transfusion related acute lung injury. Alternatively, she was treated with immunoadsorption plasmapheresis. Her symptoms were significantly improved. This case seems to be valuable because there are few reports showing effectiveness of immunoadsorption therapy on anti-MOG antibody-related diseases, especially for polyphasic disseminated encephalomyelitis.

Comparison of live and fixed cell-based assay performance: implications for the diagnosis of MOGAD in a low-middle income country

Background

Though considered optimal, live cell-based assay (LCBA) is often unavailable for the diagnosis of myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD) in resource-poor regions. This study was undertaken to determine the agreement between LCBA and the widely available fixed cell-based assay (FCBA), for recommending testing guidelines within our region.

Method

All consecutive patients in our registry with a MOGAD phenotype were tested. The results from a commercially available FCBA (Euroimmun, Germany) were compared with a validated "in-house" LCBA. Clinical and MRI data were available for correlation.

Results

Among the 257 patient samples tested, 118 (45.9%) were positive by FCBA titre ≥1: 10 and or LCBA titres ≥1: 160 titre and 139 samples were negative. There was robust agreement between the two assays (agreement 98.8%, Cohen's kappa 0.98 [95% CI- 0.95-1.00], Spearman correlation 0.97 (p < 0.0001). Among five discordant samples, four had clinical and or MRI data which supported an alternate diagnosis. There was a modest correlation between assay titres, particularly for samples with titres ≥ 1:100 in FCBA (Spearman's Rho 0.26, p 0.005). Thirty samples were positive by FCBA at < 1:100 titre and included 1:80 (20),1:40(7) and 1:10 (3) titres. Among them, 80% had clear positive titres when tested by LCBA.

Conclusion

The FCBA tested with serum dilutions of 1:10 was highly predictive of MOGAD in our study and compared well with our "in-house" LCBA. The current recommendations for testing at higher dilutions need to be re-examined in light of our findings. The results of our study should ideally be replicated in a larger dataset but at the same time provide some guidance for the accurate diagnosis of MOGAD in resource-poor settings.

Intravenous immunoglobulin treatment for acute attacks in myelin oligodendrocyte glycoprotein antibody disease

BACKGROUND

The potential therapeutic benefit of intravenous immunoglobulins (IVIGs) for acute attacks of myelin oligodendrocyte glycoprotein antibody disease (MOGAD) is unknown.

OBJECTIVE

The objective was to describe the outcomes of IVIG treatment for acute MOGAD attacks.

METHODS

A retrospective observational study involving seven tertiary neuroimmunology centers. Data collection included patients' demographics, Expanded Disability Status Scale (EDSS), and visual acuity (VA) before the attack, at the nadir of the attack before IVIG treatment, and at follow-up visits ⩾3 months after treatment.

RESULTS

Thirty-nine patients were included, of which 21 (53.8%) were female. The median age was 23 years (range 5-74 years), and the median disease duration was 4 months (range 0-93 months). The most common type of attack treated with IVIG was isolated optic neuritis (ON) (unilateral n = 14, bilateral n = 5, associated with transverse myelitis (TM), n = 1), followed by acute disseminated encephalomyelitis (ADEM) (n = 8), multifocal (n = 7), TM (n = 3), brainstem (n = 1), and other encephalitis (n = 1). A significant improvement in both the EDSS and VA measures was observed at follow-up compared to the time of IVIG treatment initiation (p < 0.0001 for both outcome measures).

CONCLUSION

IVIG may be an effective treatment option for acute MOGAD attacks. Further prospective studies are warranted to validate our results.

The neuro-ophthalmological manifestations of NMOSD and MOGAD-a comprehensive review

Optic neuritis (ON) is one of the most frequently seen neuro-ophthalmic causes of vision loss worldwide. Typical ON is often idiopathic or seen in patients with multiple sclerosis, which is well described in the landmark clinical trial, the Optic Neuritis Treatment Trial (ONTT). However, since the completion of the ONTT, there has been the discovery of aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) antibodies, which are biomarkers for neuromyelitis optica spectrum disorder (NMOSD) and MOG antibody-associated disease (MOGAD), respectively. These disorders are associated with atypical ON that was not well characterised in the ONTT. The severity, rate of recurrence and overall outcome differs in these two entities requiring prompt and accurate diagnosis and management. This review will summarise the characteristic neuro-ophthalmological signs in NMOSD and MOGAD, serological markers and radiographic findings, as well as acute and long-term therapies used for these disorders.

High level of agreement in a fixed vs. live cell-based assay for antibodies to myelin oligodendrocyte glycoprotein in a real-world clinical laboratory setting

Introduction

As recognition of myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease becomes more widespread, the importance of appropriately ordering and interpreting diagnostic testing for this antibody increases. Several assays are commercially available for MOG testing, and based on a few small studies with very few discrepant results, some have suggested that live cell-based assays (CBA) are superior to fixed CBA for clinical MOG antibody testing. We aimed to determine the real-world agreement between a fixed and live CBA for MOG using two of the most commonly available commercial testing platforms.

Methods

We compared paired clinical samples tested at two national clinical reference laboratories and determined the real-world agreement between the fixed CBA and live CBA.

Results

Of 322 paired samples tested on both platforms, 53 were positive and 246 were negative by both methodologies (agreement 92.9%, Cohen's kappa 0.78, [0.69-0.86]). Spearman correlation coefficient was 0.80 (p < 0.0001). Of the discrepant results, only 1 of 14 results positive by the live CBA had a titer greater than 1:100, and only 1 of 9 results positive by the fixed CBA had a titer of greater than 1:80. Lower titers on the fixed CBA correlate to higher titers on the live CBA.

Conclusion

Overall, there is excellent agreement between fixed and live CBA for MOG antibody testing in a real-world clinical laboratory setting. Clinicians should be aware of which method they use to assess any given patient, as titers are comparable, but not identical between the assays.

Transverse myelitis in myelin oligodendrocyte glycoprotein antibody-associated disease

Transverse myelitis (TM) is the second most common presentation of myelin oligodendrocyte antibody-associated disease (MOGAD), occurring in approximately 26% of affected patients. The diagnosis may be complicated by the lack of diagnostic specificity of low titers of MOG antibody in serum, fluctuation in seropositivity overtime, including initially normal MRI in up to 10% of patients, and in many instances complete resolution of radiological abnormalities when MRI is done in a significantly delayed fashion. The use of preventive disease modifying treatments is limited by the uncertainty whether the disease process will remain monophasic or become relapsing, as well as by the lack FDA approved treatments. In this review, we discuss clinical, radiological and cerebrospinal fluid (CSF) characteristics, including the significance of MOG titers and changes in the seropositivity status for the diagnosis of MOGAD-associated TM, its radiological features and management options, highlighting the data on the risk of relapses associated with TM at presentation and the need for further randomized clinical trials to empower effective treatment algorithms.

Myelin Oligodendrocyte Glycoprotein (MOG) Associated Diseases: Updates in Pediatric Practice

Myelin oligodendrocyte glycoprotein (MOG) is a membrane bound protein found on the surface of oligodendrocyte cells and the outermost surface of myelin sheaths. MOG is posited to play a role as a cell surface receptor or cell adhesion molecule, though there is no definitive answer to its exact function at this time. In the last few decades, there has been a recognition of anti-MOG-antibodies (MOG-Abs) in association with a variety of neurologic conditions, though primarily demyelinating and white matter disorders. In addition, MOG associated disease (MOGAD) appears to have a predilection for pediatric populations and in some patients may have a relapsing course. There has been considerable debate as to whether MOG-Abs are truly directly pathogenic or a disease biomarker associated with neuorinflammatory disease. In this manuscript we will review the current literature surrounding MOGAD, review new clinical phenotypes, discuss treatment and prognosis, and provide insight into potential future directions that studies may focus on.

Subclinical optic neuritis in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND AND OBJECTIVES

The clinical spectrum of myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is heterogenous and has evolved over time since the commercial availability of the anti-MOG antibody assay. Subclinical disease activity has been previously reported in the visual pathway, but prevalence data remains limited. We investigated subclinical optic neuritis (ON) based on changes on retinal nerve fiber layer (RNFL) thickness on optic coherence tomography (OCT) in pediatric patients who tested positive for the anti-MOG antibody.

METHODS

In this retrospective, single-center cohort study, we examined children with MOGAD with at least one complete assessment of the anterior visual pathway. Subclinical ON was defined by structural visual system disease in the absence of a subjective complaint of vision loss, pain (particularly with eye movement), or color desaturation.

RESULTS

Records were reviewed from 85 children with MOGAD, 67 of whom (78.8%) had complete records for review. Eleven children (16.4%) had subclinical ON on OCT. Ten had significant reductions in RNFL, of which one had two distinct episodes of decreased RNFL, and one had significant elevations in RNFL. Of the eleven children with subclinical ON, six (54.5%) had a relapsing disease course. We also highlighted the clinical course of three children with subclinical ON detected on longitudinal OCT, including two who had subclinical ON outside of clinical relapses.

CONCLUSION

Children with MOGAD can have subclinical ON events that can manifest as significant reductions or elevations in RNFL on OCT. OCT should be used routinely in the management and monitoring of MOGAD patients.

MOGAD patient autoantibodies induce complement, phagocytosis, and cellular cytotoxicity

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an inflammatory demyelinating CNS condition characterized by the presence of MOG autoantibodies. We sought to investigate whether human MOG autoantibodies are capable of mediating damage to MOG-expressing cells through multiple mechanisms. We developed high-throughput assays to measure complement activity (CA), complement-dependent cytotoxicity (CDC), antibody-dependent cellular phagocytosis (ADCP), and antibody-dependent cellular cytotoxicity (ADCC) of live MOG-expressing cells. MOGAD patient sera effectively mediate all of these effector functions. Our collective analyses reveal that (a) cytotoxicity is not incumbent on MOG autoantibody quantity alone; (b) engagement of effector functions by MOGAD patient serum is bimodal, with some sera exhibiting cytotoxic capacity while others did not; (c) the magnitude of CDC and ADCP is elevated closer to relapse, while MOG-IgG binding is not; and (d) all IgG subclasses can damage MOG-expressing cells. Histopathology from a representative MOGAD case revealed congruence between lesion histology and serum CDC and ADCP, and we identified NK cells, mediators of ADCC, in the cerebrospinal fluid of relapsing patients with MOGAD. Thus, MOGAD-derived autoantibodies are cytotoxic to MOG-expressing cells through multiple mechanisms, and assays quantifying CDC and ADCP may prove to be effective tools for predicting risk of future relapses.

Clinical course, imaging, and pathological features of 45 adult and pediatric cases of myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a recently described neuroinflammatory demyelinating disease.

OBJECTIVE

To better understand the clinical spectrum, risk factors and outcomes in MOGAD.

METHODS

Retrospective cohort study including all subjects harboring anti-MOG antibodies identified in major academic hospitals across the province of Quebec.

RESULTS

We identified 45 MOGAD cases. The minimal estimated point-prevalence was 0.52/100 000 in Quebec. Median age at presentation was 32 years (range 1-71) with equal sex ratio. Most frequent ethnic groups were Caucasians and Asians. The most frequent clinical manifestations at onset were optic neuritis (ON), affecting 56% of adults, and acute disseminated encephalomyelitis (ADEM), affecting 33% of children. First MRI was abnormal in 84% of cases. Most CSF samples showed pleocytosis without oligoclonal bands. Two brain biopsies revealed lipid-laden macrophages and reactive astrocytes. Despite steroids, only 38% had fully recovered at 4 weeks after onset. Half of pediatric and two thirds of adult-onset MOGAD subjects experienced relapses. At last follow-up, 69% showed residual deficits, which were moderate to severe in 17% of adults.

CONCLUSION

MOGAD has heterogeneous disease course, and it is not a benign disease for a substantial proportion of adults. Best disease-modifying therapies remain to be determined.

MRI pattern in acute optic neuritis: Comparing multiple sclerosis, NMO and MOGAD

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.

Skin Manifestations of Neuromyelitis Optica Spectrum Disorder With Secondary Systemic Lupus Erythematosus During Pregnancy: A Three-Year Follow-Up

Neuromyelitis optica spectrum disorder (NMOSD) is a disease of the central nervous system and the optic nerves that disproportionately affects women and occasionally coexists with other autoimmune diseases. NMOSD manifesting as skin lesions is a rare phenomenon. Furthermore, these skin lesions in the setting of NMOSD during pregnancy have not been described. We report the case of a 31-year-old woman from sub-Saharan Africa who presented with initial recurrent skin lesions followed by paraparesis during her second trimester of pregnancy. Her next pregnancy was associated with sudden vision loss. She had positive serology for aquaporin-4 antibodies and subsequently developed a positive dsDNA antibody two years after the initial NMOSD diagnosis. Her skin lesions and symptoms improved following the administration of azathioprine. This case highlights the impact of pregnancy on NMOSD and the significance of a heightened level of suspicion for NMOSD in patients who exhibit recurring skin lesions preceding paraparesis events.

AQP4-IgG NMOSD, MOGAD, and double-seronegative NMOSD: is it possible to depict the antibody subtype using magnetic resonance imaging?

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.

Clinical, radiological, therapeutic and prognostic differences between MOG-seropositive and MOG-seronegative pediatric acute disseminated encephalomyelitis patients: a retrospective cohort study

Objective

This study aimed to compare the clinical, radiological, therapeutic, and prognostic differences between pediatric patients showing acute disseminated encephalomyelitis (ADEM) with and without myelin oligodendrocyte glycoprotein (MOG) antibodies.

Methods

We retrospectively collected all available data of children diagnosed with ADEM and tested for serum MOG antibodies at the Children's Hospital of Chongqing Medical University from January 2017 to May 2021.

Results

A total of 62 patients were included in our cohort, of which 35 were MOG-seropositive and 27 were MOG-seronegative. MOG-seropositive ADEM children presented with significantly lower rates of seizures (P = 0.038) and cranial nerve (III-XII) palsy (P = 0.003). Isolated leukocytosis in the blood was more common in ADEM children with MOG antibodies (P < 0.001). The two groups showed no significant differences in the distributions and extent of the MRI lesions as well as the appearance of typical/atypical magnetic resonance imaging (MRI) features. MOG-seropositive children were more likely to relapse (P = 0.017) despite having slower oral prednisolone tapering after acute treatments (P = 0.028). In scoring performed on the basis of two neurological function scoring systems, MOG-seropositive children showed milder neurological disability status at onset (P = 0.017 and 0.025, respectively) but showed no difference during follow-up.

Conclusion

In summary, the differences in the clinical manifestations and auxiliary examination findings for MOG-seropositive and MOG-seronegative ADEM children lacked significance and specificity, making early identification difficult. MOG-seropositive children were more likely to relapse and showed slower steroid tapering. Moreover, MOG-seronegative children tended to have more severe neurological impairments at onset with no difference during follow-up.

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD): current understanding and challenges

New diagnostic criteria for myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) have recently been proposed, distinguishing this syndrome from other inflammatory diseases of the central nervous system. Seropositivity status for MOG-IgG autoantibodies is important for diagnosing MOGAD, but only in the context of robust clinical characterization and cautious interpretation of neuroimaging. Over the last several years, access to cell-based assay (CBA) techniques has improved diagnostic accuracy, yet the positive predictive value of serum MOG-IgG values varies with the prevalence of MOGAD in any given patient population. For this reason, possible alternative diagnoses need to be considered, and low MOG-IgG titers need to be carefully weighted. In this review, cardinal clinical features of MOGAD are discussed. Key challenges to the current understanding of MOGAD are also highlighted, including uncertainty regarding the specificity and pathogenicity of MOG autoantibodies, the need to identify immunopathologic targets for future therapies, the quest to validate biomarkers that facilitate diagnosis and detect disease activity, and the importance of deciphering which patients with MOGAD require long-term immunotherapy.

Neuromyelitis Optica: A Case Report From a Radiological Perspective

Neuromyelitis optica (NMO), also known as Devic's disease, is a chronic inflammatory disorder of the optic nerve and the spinal cord. Similar to multiple sclerosis, it has a relapsing and remitting characteristic. The disease is characterized by optic neuritis and longitudinal extensive inflammation of the spinal cord. Magnetic resonance imaging (MRI) is the modality of choice for this disorder. The serological examination also shows the presence of aquaporin-4 (AQP4) autoantibodies. MRI shows longitudinal extensive transverse myelitis and signs of optic neuritis such as inflammation of the optic nerve. The treatment is based on intravenous corticosteroids with or without plasmapheresis. The current case is a 25-year-old African American male patient who presented with multiple sclerosis-like symptoms (i.e., optic neuritis and transverse myelitis) but turned out to have NMO. Serological examination reveals the absence of AQP4 autoantibodies. A radiological examination showed swelling in the cervical cord. This case report strongly focuses on the radiological findings of NMO.

Systematic Review of Treatment Options and Therapeutic Responses for Lesions of the Sella and Orbit: Evidence-Based Recommendations

OBJECTIVE

Inflammatory pathologies of the sella and orbit are rare but require prompt diagnosis to initiate effective treatment. Because uniform recommendations for treatment are currently lacking, we performed an evidence-based review to identify recommendations.

METHODS

We performed a literature search of the PubMed, Embase, and Web of Science databases to identify papers evaluating treatment of inflammatory pathologies of the sella and orbit. We used PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to define recommendations, specifically examining aggregated sample sizes, disease-specific patient follow-up, and clinical trials focused on inflammatory diseases of the sella and orbit.

RESULTS

A total of 169 studies were included and organized by disease pathology. Treatments for various pathologies were recorded. Treatment options included surgery, radiation, steroids, targeted treatments, immunomodulators, intravenous immune globulin, and plasmapheresis. Steroids were the most often employed treatment, second-line management options and timing varied. Pathological diagnosis was highly associated with treatment used. Most evidence were level 3 without available control groups, except for 13 trials in neuromyelitis optica with level 1 or 2 evidence.

CONCLUSIONS

This is the first evidence-based review to provide recommendations on specific treatments for pathologies of the orbit and sella. The reported data may be useful to help guide randomized clinical trials and provide resource for clinical management decisions based on the available evidence.

Clinical characteristics and prognosis of optic neuritis in Taiwan - a hospital-based cohort study

BACKGROUND

Optic neuritis (ON) is an inflammatory disease of optic nerve. The distinct etiologies of ON significantly influence its clinical manifestation, neuroimaging findings, and visual outcomes. However, the clinical characteristics might be influenced by the racial differences. The purpose of this study is to investigate the clinical characteristics of various types of ON at a Taiwanese tertiary center.

METHODS

This cohort study analyzed 163 patients who received treatment and continued following-up for ON between 2015 and 2022. We selected patients who had been tested for anti-aquaporin-4 antibody (AQP4-Ab) and anti-myelin oligodendrocyte glycoprotein antibody (MOG-Ab). The participants were classified into four groups on the basis of their etiologies, specifically (1) multiple sclerosis (MS)-related, (2) AQP4-Ab-positive, (3) MOG-Ab-positive, or (4) idiopathic ON. The researchers recorded the patients' clinical characteristics, treatment course, magnetic resonance imaging and optical coherence tomography (OCT) findings, and visual outcomes.

RESULTS

MOG-Ab-positive group had higher percentages of disk swelling and pain with eye movement. Long optic nerve and perineural enhancement are the hallmarks of MOG-Ab-related ON. The ON relapse rate was higher in AQP4-Ab-positive group. Although members of AQP4-Ab-positive group received immediate steroid pulse therapy, these patients experienced the worst visual outcomes. Moreover, a thinner retinal nerve fiber layer (RNFL) was noted in AQP4-Ab-positive group. MS group had a higher incidence of extra-optic nerve lesions. Multivariate regression identified pretreatment visual acuity and RNFL thickness as the important factors affecting visual outcomes.

CONCLUSIONS

This cohort study identified the clinical features of different types of ON. Patients with AQP4-Ab-positive ON had poorer visual outcomes, which may be attributed to multiple relapses and profound nerve damage, as revealed by OCT findings. Patients with MOG-Ab-positive ON displayed long optic nerve enhancement but had more favorable prognoses. Thus, antibody-based classification facilitates treatment and prognosis in ON.

Update on the diagnosis and treatment of neuromyelits optica spectrum disorders (NMOSD) - revised recommendations of the Neuromyelitis Optica Study Group (NEMOS). Part I: Diagnosis and differential diagnosis

The term 'neuromyelitis optica spectrum disorders' (NMOSD) is used as an umbrella term that refers to aquaporin-4 immunoglobulin G (AQP4-IgG)-positive neuromyelitis optica (NMO) and its formes frustes and to a number of closely related clinical syndromes without AQP4-IgG. NMOSD were originally considered subvariants of multiple sclerosis (MS) but are now widely recognized as disorders in their own right that are distinct from MS with regard to immunopathogenesis, clinical presentation, optimum treatment, and prognosis. In part 1 of this two-part article series, which ties in with our 2014 recommendations, the neuromyelitis optica study group (NEMOS) gives updated recommendations on the diagnosis and differential diagnosis of NMOSD. A key focus is on differentiating NMOSD from MS and from myelin oligodendrocyte glycoprotein antibody-associated encephalomyelitis (MOG-EM; also termed MOG antibody-associated disease, MOGAD), which shares significant similarity with NMOSD with regard to clinical and, partly, radiological presentation, but is a pathogenetically distinct disease. In part 2, we provide updated recommendations on the treatment of NMOSD, covering all newly approved drugs as well as established treatment options.

Low mortality rate in a large cohort of myelin oligodendrocyte glycoprotein antibody disease (MOGAD)

The mortality rates of individuals with myelin oligodendrocyte glycoprotein antibody disease (MOGAD) are currently unknown. This study aimed to assess the mortality rate in a large cohort of patients with MOGAD. Since none of the patients in our cohort died, we estimated the upper limit of a 95% confidence interval of the crude mortality rate in the cohort to be 2.1%. These data suggest that mortality in MOGAD is lower than that reported in other neuroinflammatory diseases and comparable to the age-adjusted mortality rates of the general population in the United States. Additional studies are warranted to confirm this observation.

Successful treatment with subcutaneous ofatumumab in an adolescent patient with refractory myelin oligodendrocyte glycoprotein-immunoglobulin G-associated disease (MOGAD)

Preventing relapse of myelin oligodendrocyte glycoprotein-immunoglobulin G-associated disease (MOGAD) with steroids and immunosuppressants is sometimes difficult. There is no standard treatment for refractory cases. We present the case of a 17-year-old female patient with longitudinally extensive myelitis, asymptomatic bilateral optic neuritis, and positive serum MOG-IgG. While taking steroids and several immunosuppressants during the following 14 months, she suffered from two symptomatic relapses in the cerebrum and spinal cord, and multiple asymptomatic relapses in the cerebrum. The patient was negative for MOG-IgG at the second relapse of myelitis. Subcutaneous ofatumumab has suppressed relapse for 13 months. Ofatumumab can be considered a therapeutic option for refractory MOGAD.

The Postpartum Period Can Worsen Myelin Oligodendrocyte Glycoprotein Antibody-associated Encephalomyelitis

Myelin oligodendrocyte glycoprotein (MOG) antibodies are associated with relapsing inflammatory demyelinating disease. Pregnancy complicates the disease course, potentially leading to either symptom improvement or worsening. A 28-year-old woman with MOG antibody-associated encephalomyelitis had 2 pregnancies; her disease worsened during both postpartum periods despite continuing prednisolone and levetiracetam. The umbilical cord blood was positive for MOG antibodies following her second pregnancy, but neither baby had MOG antibody-associated disease. This is the first case report of MOG antibody-associated demyelinating disease that worsened postpartum despite continuous medication. Furthermore, we observed the placental transfer of MOG antibodies for the first time.

Clinical and Radiologic Features Among Children With Myelin Oligodendrocyte Glycoprotein Antibody-Associated Myelitis

BACKGROUND

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) often manifests as optic neuritis, transverse myelitis(TM), and acute disseminated encephalomyelitis. Patients with a TM phenotype are at high risk for neurological sequelae, so recognizing the characteristics of MOG-IgG myelitis is essential for early, accurate diagnosis and treatment.

METHODS

This was a single-center retrospective study. Pediatric MOG antibody-associated disease patients who had clinical myelitis were recruited for this study. Data on clinical and radiologic features and outcomes were retrospectively collected.

RESULTS

Thirty-four patients (age range: 6 months to 13 years; median age, 7 years; female, 16) were enrolled in this study. As one patient had two clinical episodes of myelitis, 35 episodes were included. Isolated transverse myelitis was the initial manifestation in 28 (82%) patients. The most frequent clinical features of MOG-IgG myelitis were weakness and neurogenic bladder, and 80% were better than wheelchair-dependent at the nadir. There was a high presentation of weakness (91%), bowel/bladder dysfunction (63%), and sensory dysfunction (46%), and 80% were better than wheelchair-dependent at the nadir. In addition, seven patients (20%) had radicular pain, and six had flaccid areflexia. Magnetic resonance imaging features were often longitudinally extensive (63%) and prominently involved gray matter (H-sign) (63%), accompanied by leptomeningeal enhancement (4/14.29%) and spinal root enhancement (6/14.43%). At the final follow-up (median, 28 months; range, 8-109 months), 10 patients (29%) had developed one or more relapses, spinal cord lesions resolved entirely in 11 of 22 children (50%), and none had appreciable spinal cord atrophy. At the final follow-up, most patients had favorable outcomes, with median (interquartile range) Expanded Disability Status Scale scores of 0 (range, 0-2), four patients (12%) had sphincter dysfunction, and one patient had gait problems.

CONCLUSIONS

Pediatric MOG-IgG myelitis clinically presents with weakness and bowel and bladder dysfunctions. Prominent involvement of the gray matter, leptomeningeal enhancement, and spinal root enhancement are common in pediatric MOG-IgG myelitis.

Encephalopathy after COVID-19 vaccination during treatment with nivolumab: A case report

Vaccination is useful for the prevention of COVID-19 and is recommended for everyone, especially people with a weakened immune system. However, various neurological complications have been reported following vaccination. Here, we report the case of a 25 years-old, Japanese man, who presented with acute encephalopathy two days after the second dose of the COVID-19 vaccine. He had been treated with nivolumab, a medication used to treat cancer. He had a high fever and was confused upon admission, and the antibody test was positive for anti-myelin oligodendrocyte glycoproteins. Abnormal signal intensity at the splenium corporis callosi was observed on diffusion-weighted imaging of the brain. We diagnosed him with autoimmune encephalitis and initiated intravenous methylprednisolone, after which, the patient's symptoms rapidly subsided.

The Potential Pathogenicity of Myelin Oligodendrocyte Glycoprotein Antibodies in the Optic Pathway

BACKGROUND

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an acquired inflammatory demyelinating disease with optic neuritis (ON) as the most frequent clinical symptom. The hallmark of the disease is the presence of autoantibodies against MOG (MOG-IgG) in the serum of patients. Whereas the role of MOG in the experimental autoimmune encephalomyelitis animal model is well-established, the pathogenesis of the human disease and the role of human MOG-IgG is still not fully clear.

EVIDENCE ACQUISITION

PubMed was searched for the terms "MOGAD," "optic neuritis," "MOG antibodies," and "experimental autoimmune encephalomyelitis" alone or in combination, to find articles of interest for this review. Only articles written in English language were included and reference lists were searched for further relevant papers.

RESULTS

B and T cells play a role in the pathogenesis of human MOGAD. The distribution of lesions and their development toward the optic pathway is influenced by the genetic background in animal models. Moreover, MOGAD-associated ON is frequently bilateral and often relapsing with generally favorable visual outcome. Activated T-cell subsets create an inflammatory environment and B cells are necessary to produce autoantibodies directed against the MOG protein. Here, pathologic mechanisms of MOG-IgG are discussed, and histopathologic findings are presented.

CONCLUSIONS

MOGAD patients often present with ON and harbor antibodies against MOG. Furthermore, pathogenesis is most likely a synergy between encephalitogenic T and antibody producing B cells. However, to which extent MOG-IgG are pathogenic and the exact pathologic mechanism is still not well understood.

Diagnosis of myelin oligodendrocyte glycoprotein antibody-associated disease: International MOGAD Panel proposed criteria

Serum antibodies directed against myelin oligodendrocyte glycoprotein (MOG) are found in patients with acquired CNS demyelinating syndromes that are distinct from multiple sclerosis and aquaporin-4-seropositive neuromyelitis optica spectrum disorder. Based on an extensive literature review and a structured consensus process, we propose diagnostic criteria for MOG antibody-associated disease (MOGAD) in which the presence of MOG-IgG is a core criterion. According to our proposed criteria, MOGAD is typically associated with acute disseminated encephalomyelitis, optic neuritis, or transverse myelitis, and is less commonly associated with cerebral cortical encephalitis, brainstem presentations, or cerebellar presentations. MOGAD can present as either a monophasic or relapsing disease course, and MOG-IgG cell-based assays are important for diagnostic accuracy. Diagnoses such as multiple sclerosis need to be excluded, but not all patients with multiple sclerosis should undergo screening for MOG-IgG. These proposed diagnostic criteria require validation but have the potential to improve identification of individuals with MOGAD, which is essential to define long-term clinical outcomes, refine inclusion criteria for clinical trials, and identify predictors of a relapsing versus a monophasic disease course.

Origins and immunopathogenesis of autoimmune central nervous system disorders

The field of autoimmune neurology is rapidly evolving, and recent discoveries have advanced our understanding of disease aetiologies. In this article, we review the key pathogenic mechanisms underlying the development of CNS autoimmunity. First, we review non-modifiable risk factors, such as age, sex and ethnicity, as well as genetic factors such as monogenic variants, common variants in vulnerability genes and emerging HLA associations. Second, we highlight how interactions between environmental factors and epigenetics can modify disease onset and severity. Third, we review possible disease mechanisms underlying triggers that are associated with the loss of immune tolerance with consequent recognition of self-antigens; these triggers include infections, tumours and immune-checkpoint inhibitor therapies. Fourth, we outline how advances in our understanding of the anatomy of lymphatic drainage and neuroimmune interfaces are challenging long-held notions of CNS immune privilege, with direct relevance to CNS autoimmunity, and how disruption of B cell and T cell tolerance and the passage of immune cells between the peripheral and intrathecal compartments have key roles in initiating disease activity. Last, we consider novel therapeutic approaches based on our knowledge of the immunopathogenesis of autoimmune CNS disorders.

A unified classification approach rating clinical utility of protein biomarkers across neurologic diseases

A major evolution from purely clinical diagnoses to biomarker supported clinical diagnosing has been occurring over the past years in neurology. High-throughput methods, such as next-generation sequencing and mass spectrometry-based proteomics along with improved neuroimaging methods, are accelerating this development. This calls for a consensus framework that is broadly applicable and provides a spot-on overview of the clinical validity of novel biomarkers. We propose a harmonized terminology and a uniform concept that stratifies biomarkers according to clinical context of use and evidence levels, adapted from existing frameworks in oncology with a strong focus on (epi)genetic markers and treatment context. We demonstrate that this framework allows for a consistent assessment of clinical validity across disease entities and that sufficient evidence for many clinical applications of protein biomarkers is lacking. Our framework may help to identify promising biomarker candidates and classify their applications by clinical context, aiming for routine clinical use of (protein) biomarkers in neurology.

Anti-myelin Oligodendrocyte Glycoprotein Antibody-positive Myelitis after Coronavirus Disease 2019

We herein report a case of anti-myelin oligodendrocyte glycoprotein (MOG) antibody-related myelitis caused by coronavirus disease (COVID-19) infection in 2021. A 22-year-old man with no history of any related illness contracted COVID-19. Eight days later, he developed bladder problems, paraplegia and sensory disturbances. Cervical spinal cord magnetic resonance imaging revealed extensive hyperintensity at T2 and spinal cord lesions extending from C4 to Th1. The patient was diagnosed with transverse myelitis and started on intravenous methylprednisolone, plasma exchange and intravenous immunoglobulin therapy. The symptoms improved only after intravenous methylprednisolone therapy. Anti-MOG antibodies were found in his serum and cerebrospinal fluid during routine screening. As this observation is unusual and could cause serious health problems, we wonder if COVID-19 triggered this autoimmune response.

Prognostic relevance of quantitative and longitudinal MOG antibody testing in patients with MOGAD: a multicentre retrospective study

BACKGROUND

IgG antibodies against myelin oligodendrocyte glycoprotein (MOG-IgG) define a subset of associated disorders (myelin oligodendrocyte glycoprotein associated disorders (MOGAD)) that can have a relapsing course. However, information on relapse predictors is scarce. The utility of retesting MOG-IgG over time and measuring their titres is uncertain. We aimed to evaluate the clinical relevance of longitudinal MOG-IgG titre measurement to predict relapses in patients with MOGAD.

METHODS

In this retrospective multicentre Italian cohort study, we recruited patients with MOGAD and available longitudinal samples (at least one >3 months after disease onset) and tested them with a live cell-based assay with endpoint titration (1:160 cut-off). Samples were classified as 'attack' (within 30 days since a disease attack (n=59, 17%)) and 'remission' (≥31 days after attack (n=295, 83%)).

RESULTS

We included 102 patients with MOGAD (57% adult and 43% paediatric) with a total of 354 samples (83% from remission and 17% from attack). Median titres were higher during attacks (1:1280 vs 1:640, p=0.001). Median onset titres did not correlate with attack-related disability, age or relapses. Remission titres were higher in relapsing patients (p=0.02). When considering the first remission sample available for each patient, titres >1:2560 were predictors of relapsing course in survival (log rank, p<0.001) and multivariate analysis (p<0.001, HR: 10.9, 95% CI 3.4 to 35.2). MOG-IgG seroconversion to negative was associated with a 95% relapse incidence rate reduction (incidence rate ratio: 0.05, p<0.001).

CONCLUSIONS

Persistent MOG-IgG positivity and high remission titres are associated with an increased relapse risk. Longitudinal MOG-IgG titres could be useful to stratify patients to be treated with long term immunosuppression.

Meta-analysis of the effectiveness of relapse prevention therapy for myelin-oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND

Approximately 40% of adults and 30% of children with Myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD) experience a relapsing course, but the optimal relapse prevention therapy remains unclear. A meta- analysis was conducted to investigate the efficacy of azathioprine (AZA), mycophenolate mofetil (MMF), rituximab (RTX), maintenance intravenous immunoglobulin (IVIG), and tocilizumab (TCZ) in prevention of attacks in MOGAD.

METHODS

English and Chinese-language articles published from January 2010 to May 2022 were searched in PubMed, Embase, Web of Science, Cochrane, Wanfang Data, China National Knowledge Infrastructure (CNKI), and China Science and Technology Journal Database (CQVIP). Studies with fewer than three cases were excluded. Meta-analysis of the relapse-free rate, the change of annualized relapse rate (ARR)and Expanded Disability Status Scale (EDSS) scores before and after treatment, and an age subgroup analysis was performed.

RESULTS

A total of 41 studies were included. Three were prospective cohort studies, one was an ambispective cohort study, and 37 were retrospective cohort studies or case series. Eleven, eighteen, eighteen, eight, and two studies were included in the meta-analysis for relapse-free probability after AZA, MMF, RTX, IVIG, and TCZ therapy, respectively. The proportions of patients without relapse after AZA, MMF, RTX, IVIG, and TCZ were 65% [95% confidence interval (CI):49%-82%]), 73% (95%CI:62%-84%), 66% (95%CI:55%-77%), 79% (95%CI:66%-91%), and 93% (95%CI:54%-100%), respectively. The relapse-free rate did not significantly differ between the children and adults treated with each medication. Six, nine, ten, and three studies were included in the meta-analysis for the change of ARR before and after AZA, MMF, RTX, and IVIG therapy, respectively. ARR was significantly decreased after AZA, MMF, RTX, and IVIG therapy with a mean reduction of 1.58 (95%CI: [-2.29--0.87]), 1.32 (95%CI: [-1.57--1.07]), 1.01 (95%CI: [-1.34--0.67]), and 1.84 (95%CI: [-2.66--1.02]), respectively. The change in ARR did not significantly differ between children and adults.

CONCLUSIONS

AZA, MMF, RTX, maintenance IVIG, and TCZ all reduce the risk of relapse in both pediatric and adult patients with MOGAD. The literatures included in the meta-analysis were mainly retrospective studies, so large randomized prospective clinical trials are needed to compare the efficacy of different treatments.

Prophylactic Glatiramer Acetate Treatment Positively Attenuates Spontaneous Opticospinal Encephalomyelitis

Background: Glatiramer acetate (GA) is a well-established treatment option for patients with clinically isolated syndrome and relapsing-remitting multiple sclerosis (MS) with few side effects. The double transgenic mouse model spontaneous opticospinal encephalomyelitis (OSE), based on recombinant myelin oligodendrocyte glycoprotein_35-55 reactive T and B cells, mimicks features of chronic inflammation and degeneration in MS and related disorders. Here, we investigated the effects of prophylactic GA treatment on the clinical course, histological alterations and peripheral immune cells in OSE. Objective: To investigate the effects of prophylactic glatiramer acetate (GA) treatment in a mouse model of spontaneous opticospinal encephalomyelitis (OSE). Methods: OSE mice with a postnatal age of 21 to 28 days without signs of encephalomyelitis were treated once daily either with 150 µg GA or vehicle intraperitoneally (i. p.). The animals were scored daily regarding clinical signs and weight. The animals were sacrificed after 30 days of treatment or after having reached a score of 7.0 due to animal care guidelines. We performed immunohistochemistry of spinal cord sections and flow cytometry analysis of immune cells. Results: Preventive treatment with 150 µg GA i. p. once daily significantly reduced clinical disease progression with a mean score of 3.9 ± 1.0 compared to 6.2 ± 0.7 in control animals (p < 0.01) after 30 d in accordance with positive effects on weight (p < 0.001). The immunohistochemistry showed that general inflammation, demyelination or CD11c⁺ dendritic cell infiltration did not differ. There was, however, a modest reduction of the Iba1⁺ area (p < 0.05) and F4/80⁺ area upon GA treatment (p < 0.05). The immune cell composition of secondary lymphoid organs showed a trend towards an upregulation of regulatory T cells, which lacked significance. Conclusions: Preventive treatment with GA reduces disease progression in OSE in line with modest effects on microglia/macrophages. Due to the lack of established prophylactic treatment options for chronic autoimmune diseases with a high risk of disability, our study could provide valuable indications for translational medicine.

Paracentral Acute Middle Maculopathy Associated with Severe Anti-Mog (Myelin Oligodendrocyte Glycoprotein)-Positive Optic Neuritis

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.