Neuromyelitis Optica Spectrum Disorder and Anti-MOG Syndromes

Evaluating the Economic Burden of Relapses in Neuromyelitis Optica Spectrum Disorder: A Real-World Analysis Using German Claims Data

Introduction

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune disease of the central nervous system which causes recurrent relapses, resulting in blindness, paralysis, and spinal cord damage. This study sought to explore the real-world burden, treatment, and cost of NMOSD in Germany using claims data.

Methods

Our study consisted of a retrospective analysis of two anonymized health insurance datasets covering around 9 million patients in Germany from 01/01/2013 to 31/12/2019. NMOSD patients were identified using inpatient and outpatient International Classification of Diseases, Tenth Revision (ICD-10) diagnoses of neuromyelitis optica (NMO; G36.0) and relevant symptom codes. Active periods of disease were identified based on relapse events (including hospitalizations and acute treatment); healthcare resource utilization (HCRU) and direct costs were allocated to active and inactive periods based on treatment dates. Propensity score matching was used to compare HCRU and cost outcomes among patients with and without NMOSD.

Results

Overall, 130 patients were identified as having NMOSD (mean age: 46.84 years; 58% female). NMOSD patients recorded 16.52 active and 348.48 inactive days per patient year (PPY). HCRU and associated costs were approximately tenfold higher during active periods than during inactive periods, with the largest share of the cost difference driven by hospitalizations (€6424.09/€259.10 per active/inactive month) and outpatient drug prescriptions (€412.83/€271.58). Direct healthcare costs incurred by patients with NMOSD (€12,913.28 PPY) were approximately threefold higher than those incurred by patients without NMOSD (€4667.66 PPY). Costs of hospitalization (€6448.32/€1937.64 PPY) and outpatient prescriptions (€3335.67/€1037.64 PPY) contributed most strongly to the difference.

Conclusion

Patients with NMOSD consume substantial healthcare resources and incur heavy costs during active disease phases. This study captured direct measurable healthcare costs and likely underestimates the real societal/emotional burden on patients and their families. Nevertheless, prevention of acute relapses represents one compelling strategy to minimize the economic burden of NMOSD in Germany.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40120-021-00311-x.

Comparative study of AQP4 antibody-related diseases and MOG antibody-related diseases among the population in Hunan, China

To compare the clinical, imaging, and prognostic characteristics of AQP4 antibody-related diseases and MOG antibody-related diseases. The clinical data of 56 AQP4 antibody-positive patients and 14 MOG antibody-positive patients in the Second Xiangya Hospital of Central South University from June 2016 to June 2019 were collected. 92.9% of the patients with positive AQP4 antibody were females and 64.3% of patients with positive MOG antibody were females (P = 0.004). Patients with positive AQP4 antibody were more likely to have limb movement (P < 0.001) or limb sensory dysfunction (P < 0.001), and were more likely to have limb twitching (P = 0.036). In addition, AQP4 antibody-positive patients were more likely to have positive ANA (P = 0.013) and SSA antibody (P = 0.029), Ro-52 antibody (P = 0.047), immunoglobulin (P = 0.007), thyroid antibody (P = 0.007), abnormal C3 (P = 0.011), abnormal C4 (P = 0.014) than MOG antibody-positive patients. The involvement rate of head in MOG antibody-positive patients was higher than AQP4 antibody-positive patients (P = 0.029). The severity of clinical symptoms in AQP4-positive patients was usually more serious than that in MOG-positive patients (P < 0.001). The residual neurological deficit after treatment in AQP4-positive group was usually more serious than that in MOG-positive group (P < 0.001). AQP4 antibody-positive patients had a higher prevalence in women than MOG antibody-positive patients, and AQP4 antibody-positive patients were more likely to have spinal cord involvement symptoms and connective tissue antibody abnormalities. The EDSS score of them were higher than that of MOG antibody-positive patients after treatment, and the prognosis was worse.

Phadke M. Neuromyelitis Optica Spectrum Disorder Manifested by Persistent Hiccups and Severe Esophagitis in an Adolescent Patient

Patients with persistent hiccups are often referred to gastrointestinal services. Hiccups lasting greater than 48 hours are classified as persistent, while those lasting longer than 2 months are termed intractable. The etiology of hiccups is broad and can include many organ systems. Here, we present the case of an 18-year-old male patient who presented to the emergency department with an 8-day history of nausea, emesis, and intermittent hiccups. The patient was admitted to the gastroenterology service and underwent workup including esophagogastroduodenoscopy and imaging. Esophagogastroduodenoscopy revealed severe distal esophagitis. He was started on high-dose proton pump inhibitor and sucralfate. During the course of hospital admission, the patient's intermittent hiccups worsened to become constant. Several medical therapies led to little improvement. We initially felt that the esophagitis was the etiology of the patient's symptoms, however, due to ongoing symptoms unresponsive to typical therapy, we obtained a neurological consult. Brain MRI revealed a dorsal medullary lesion. Subsequent work up confirmed the diagnosis of neuromyelitis optica spectrum disorder. Neuromyelitis optica spectrum disorder is a rare, serious, sometimes fatal autoimmune condition of the central nervous system. Early diagnosis and treatment are important predictors of future relapses. Our patient was started on high-dose intravenous steroids with rapid improvement in symptoms. He was discharged home on steroids, proton pump inhibitor and close neurology and gastroenterology follow up. This case outlines the importance of consideration of neurological causes of hiccups or other centrally mediated conditions with gastrointestinal manifestations, even when a concomitant gastrointestinal condition is present.

A Comprehensive Review on the Role of Genetic Factors in Neuromyelitis Optica Spectrum Disorder

Neuromyelitis optica spectrum disorders (NMOSD) comprise a variety of disorders being described by optic neuritis and myelitis. This disorder is mostly observed in sporadic form, yet 3% of cases are familial NMO. Different series of familial NMO cases have been reported up to now, with some of them being associated with certain HLA haplotypes. Assessment of HLA allele and haplotypes has also revealed association between some alleles within HLA-DRB1 or other loci and sporadic NMO. More recently, genome-wide SNP arrays have shown some susceptibility loci for NMO. In the current manuscript, we review available information about the role of genetic factors in NMO.

Neuroimmunology and Novel Methods of Treatment for Acute Transverse Myelitis

Acute transverse myelitis (ATM) is a rare, immune-mediated pathology that is defined as an adverse inflammatory response in the spinal cord leading to neurologic injury. The pathophysiology of ATM is poorly understood, with no apparent differences in age, ethnicities, or race, along with variable radiographic and clinical presentation. Therefore, in this review, we will characterize what is known about ATM's etiology and diagnostic criteria, and relate it to properties of neuroimmunology. Moreover, we will further discuss current treatment options, along with potential novel methods, to provide a comprehensive overview of the status of ATM's research development. Among these novel treatments, potassium blockers reveal exciting early outcomes in restoring neurologic motor function. In addition, human glial progenitor cell transportations have been described as a potential treatment through integrating and remyelinating lesion sites. Nevertheless, despite these novel methods, there is a paucity of clinical trials establishing ATM's immunopathology and the therapeutic role of potential treatment methods. Therefore, we will highlight the importance of larger well-designed clinical trials in revealing significant biomarkers of injury and recovery.

Transient Myelin Oligodendrocyte Glycoprotein Antibody-positive Acute Disseminated Encephalomyelitis Following Influenza A Infection: A Rare Case

Acute disseminated encephalomyelitis (ADEM) is an uncommon disease generally with a preceding history of infectious illness. Here, we report a rare case of ADEM following influenza A infection with transient detection of anti-myelin oligodendrocyte glycoprotein (MOG) antibody in a young male patient who presented with extensive demyelination of brain and spinal cord, likely the result of dysregulated immune response from previous influenza A infection. The patient presented to the emergency with urinary retention and progressive ascending weakness of lower limbs. Magnetic resonance imaging (MRI) of the brain and spinal cord showed multiple ill-defined hyperintensities, suggestive of demyelination. The clinical presentation, MRI findings, cerebrospinal fluid examination, negative anti-aquaporin-4 antibody and metabolic and other viral infectious screening supported the diagnosis of ADEM. The patient had transiently positive anti-MOG antibodies (for 3 months) and was treated with intravenous immunoglobulin followed by oral prednisolone for 3 months. There was a significant recovery in the upper limb weakness and brainstem function. This case highlights the association of anti-MOG antibody with ADEM following viral infections and the need for prolonged follow-up to differentiate between transient antibodies from relapsing MOG antibody disease.

Recurrent Bilateral Optic Neuritis Associated with Myelin Oligodendrocyte Glycoprotein Antibody: A Case Report from Nepal

Neuromyelitis optica spectrum disorder (NMOSD) is an immune-mediated inflammatory condition involving spinal cord and optic nerves. Diagnosis of NMOSD is done by aquaporin-4 antibody (AQP4) in patients with optic neuritis. Myelin oligodendrocyte glycoprotein (MOG) expressed on the oligodendrocyte cell surface and on the outermost cell surface of the myelin sheath may also be present in patients with NMOSD bilateral optic neuritis. Here, we describe a case of a thirty-nine-year-old-female with recurrent bilateral optic neuritis with positive anti-MOG antibody, and anti-MOG syndrome has not previously been reported from Nepal.

Autoimmune Brainstem Encephalitis: An Illustrative Case and a Review of the Literature

Autoimmune brainstem encephalitis (BSE) is a rare neurological condition with a wide range of underlying etiologies. It can be subdivided into two broad groups: a primary inflammatory disease of the central nervous system (CNS) or a brainstem disorder secondary to systemic diseases where the CNS is only one of many affected organs. Symptoms range from mild to life-threatening manifestations. Most cases respond well to immunotherapy. Therefore, broad and in-depth knowledge of the various inflammatory disorders that target the brainstem is essential for guiding the diagnostic approach and assisting in early initiation of appropriate therapy. We herein report on a case of BSE and provide an overview of the various causes of autoimmune BSE with an emphasis on the clinical manifestations and diagnostic approach.

Distinct patterns of MRI lesions in MOG antibody disease and AQP4 NMOSD: a systematic review and meta-analysis

BACKGROUND

the distinct MRI features of MOG-antibody disease (MOG-AD) and AQP4-NMOSD are still poorly defined. We performed a systematic review and meta-analysis to identify specific patterns of MRI abnormalities able to discriminate between MOG-AD and AQP4-NMOSD.

METHODS

fourteen case-series (1028 patients) were included. Outcomes were MRI lesion patterns in optic nerve (ON), brain and spinal cord (SC) that were selected after a systematic literature review and analysed separately as the event rate for individual MRI lesions in MOG-AD (experimental group) and AQP4-NMOSD (control group) by using a random effect model.

RESULTS

MOG-AD showed a higher number of MRI lesions than AQP4-NMOSD patients in the retrobulbar ON (OR=5.67; 95%CI=2.11-15.24; p=0.0006) with ON head swelling (OR=8.20; 95%CI=4.13-16.28; p<0.00001), corpus callosum (OR=2.30; 95%CI=1.11-4.76; p=0.02), pons (OR=2.87; 95%CI=1.45-5.67; p=0.002), and lumbar/conus SC (OR=3.47; 95%CI=1.66-7.24; p=0.0009). Conversely, lesions in the canalicular (OR=0.42; 95%CI=0.18-0.98; p=0.05) and intracranial ON (OR=0.30; 95%CI=0.11=0.84; p=0.02), area postrema (OR=0.12; 95%CI=0.02-0.61; p=0.01), medulla (OR=0.40; 95%CI=0.20-0.78; p=0.007), and cervical SC (OR=0.29; 95%CI=0.09-0.92; p=0.04) were prominent in patients with AQP4-NMOSD. Participants' age was found to be a source of heterogeneity across studies.

CONCLUSION

our study provides further evidence that MOG-AD and AQP4-NMOSD have distinct MRI features that may help clinicians for an early differential diagnosis.

Status of the neuromyelitis optica spectrum disorder in Latin America

BACKGROUND

Neuromyelitis optica spectrum disorders (NMOSD) is an increasing diagnostic and therapeutic challenge in Latin America (LATAM). Despite the heterogeneity of this population, ethnic and socioeconomic commonalities exist, and epidemiologic studies from the region have had a limited geographic and population outreach. Identification of some aspects from the entire region are lacking.

OBJECTIVES

To determine ethnic, clinical characteristics, and utilization of diagnostic tools and types of therapy for patients with NMOSD in the entire Latin American region.

METHODS

The Latin American Committee for Treatment and Research in MS (LACTRIMS) created an exploratory investigational survey addressed by Invitation to NMOSD Latin American experts identified through diverse sources. Data input closed after 30 days from the initial invitation. The questionnaire allowed use of absolute numbers or percentages. Multiple option responses covering 25 themes included definition of type of practice; number of NMOSD cases; ethnicity; utilization of the 2015 International Panel criteria for the diagnosis of Neuromyelitis optica (IPDN); clinical phenotypes; methodology utilized for determination of anti-Aquaporin-4 (anti- AQP4) antibodies serological testing, and if this was performed locally or processed abroad; treatment of relapses, and long-term management were surveyed.

RESULTS

We identified 62 investigators from 21 countries reporting information from 2154 patients (utilizing the IPDN criteria in 93.9% of cases), which were categorized in two geographical regions: North-Central, including the Caribbean (NCC), and South America (SA). Ethnic identification disclosed Mestizos 61.4% as the main group. The most common presenting symptoms were concomitant presence of optic neuritis and transverse myelitis in 31.8% (p=0.95); only optic neuritis in 31.4% (more common in SA), p<0.001); involvement of the area postrema occurred in 21.5% and brain stem in 8.3%, both were more frequent in the South American cases (p<0.001). Anti-AQP4 antibodies were positive in 63.9% and anti-Myelin Oligodendrocyte Glycoprotein (MOG) antibodies in 4.8% of total cases. The specific laboratorial method employed was not known by 23.8% of the investigators. Acute relapses were identified in 81.6% of cases, and were treated in 93.9% of them with intravenous steroids (IVS); 62.1% with plasma exchange (PE), and 40.9% with intravenous immunoglobulin-G (IVIG). Therapy was escalated in some cases due to suboptimal initial response. Respondents favored Rituximab as long-term therapy (86.3%), whereas azathioprine was also utilized on 81.8% of the cases, either agent used indistinctly by the investigators according to treatment accessibility or clinical judgement. There were no differences among the geographic regions.

CONCLUSIONS

This is the first study including all countries of LATAM and the largest cohort reported from a multinational specific world area. Ethnic distributions and phenotypic features of the disease in the region, challenges in access to diagnostic tools and therapy were identified. The Latin American neurological community should play a determinant role encouraging and advising local institutions and health officials in the availability of more sensitive and modern diagnostic methodology, in facilitating the the access to licensed medications for NMOSD, and addressing concerns on education, diagnosis and management of the disease in the community.

The diagnostic dilemma of bilateral optic neuritis and idiopathic intracranial hypertension coexistence in a patient with recent COVID-19 infection

Owing to autoantibody production and thrombophilic disorders in COVID-19, physicians must have low threshold to investigate secondary IIH and demyelinating disorders in patients with headache and decreased vision following recent COVID-19 infection.

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.

FTY720 Exacerbates Blood-Brain Barrier Dysfunction Induced by IgG Derived from Patients with NMO and MOG Disease

Neuromyelitis optica (NMO) and myelin oligodendrocyte glycoprotein (MOG) antibody-related disease (MOG disease) are inflammatory demyelinating diseases of the central nervous system (CNS). The disruption of the blood-brain barrier (BBB) is considered a key step in the pathogenesis of NMO and MOG disease. Although a previous report indicated that circulating immunoglobulin G (IgG) from NMO patients disrupts the BBB, the effect of IgG from patients with MOG disease has not been elucidated. In addition, it has been reported that some disease-modifying drugs for multiple sclerosis are harmful to NMO by an unknown mechanism. This study aimed to examine the effects of IgG from patients with NMO or MOG disease on BBB integrity. We also examined the effects of disease-modifying drugs (fingolimod [FTY720] and dimethyl fumarate [DMF]) on IgG-treated brain capillary endothelial cells. We used in vitro BBB models constructed with rat brain capillary endothelial cells (RBECs) to examine the effects on BBB function. The integrity of the RBECs was assessed by measuring transendothelial resistance (TEER) and cell viability. NMO or MOG-IgG treatment decreased TEER and cell viability in the endothelial monolayer model. Although FTY720 and DMF did not affect barrier function or cell viability under normal conditions, disease IgG-induced barrier dysfunctions were worsened by the presence of FTY720. These data indicate that circulating IgG in patients with NMO or MOG disease worsens BBB function. Furthermore, in patients with NMO or MOG disease treated with FTY720, changes in the integrity of the BBB were found to exacerbate the disease.

Conus involvement and leptomeningeal enhancement in aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder: A case report

There are a variety of clinical phenotypes and radiological features that continue to make a diagnosis of neuromyelitis optica spectrum disorder (NMOSD) challenging. We present an atypical case of an adult woman who presented with flaccid paralysis of all extremities with unusual neuroimaging features, including extensive enhancing lesions in the upper cervical cord and conus medullaris with associated leptomeningeal enhancement. She was ultimately found to have AQP4 antibody-positive NMOSD. We discuss the factors that complicated a timely diagnosis, including her atypical radiographic features and an initially negative cell-based assay for myelin oligodendrocyte glycoprotein (MOG) and aquaporin-4 (AQP4) antibodies. Despite the rarity of conus medullaris involvement or leptomeningeal enhancement in AQP4 antibody-positive NMOSD, it is important to maintain a high level of clinical suspicion to avoid diagnostic and therapeutic delays. Though cell-based assays have high sensitivities, testing should be repeated on negative values in these scenarios.

Myelin Oligodendrocyte Glycoprotein (MOG) Optic Neuritis: A Case Series

Myelin oligodendrocyte glycoprotein (MOG) antibody disease has been recognised as a distinct demyelinating disorder. Optic neuritis has been reported as the most common presentation and manifestation of this spectrum disorder. This is a case series of three MOG optic neuritis patients. Patients involved are female with disease onset ranging between 7- and 37-year-old. Most of these patients experienced symptoms of profound reduced visual acuity with eye pain. All three patients had optic disc swelling upon first presentation and they experienced at least one episode of bilateral simultaneous optic neuritis. Only one patient had demonstrable optic nerve enhancement on magnetic resonance imaging (MRI). Disease was confirmed through positive MOG antibody. Patients typically responded well to intravenous methylprednisolone (IVMP) during acute attack of optic neuritis. However, one patient had suboptimal response to IVMP after multiple relapses. We noted multiple relapses of optic neuritis are common in MOG patients. MOG optic neuritis is a devastating, but treatable condition. Aggressive treatment during acute optic neuritis attack and relapse prevention may favour a good visual prognosis in MOG antibody disease.

Prevalence of neuromyelitis optica spectrum disorder in Belo Horizonte, Southeast Brazil

BACKGROUND

Studies on the prevalence of neuromyelitis optica spectrum disorder (NMOSD) are still scarce. The aim of the current study was to determine the prevalence rate of NMOSD in Belo Horizonte, southeast Brazil, where the prevalence rate of multiple sclerosis (MS) has already been established.

METHODS

For this observational study, eligible patients had to meet the 2015 International Panel for Neuromyelitis Optica Diagnosis, be seen at the study center between January 2000 and February 2019 and live in Belo Horizonte. The prevalence rate of NMOSD was estimated based on the number of MS and NMOSD patients seen at same Center during the same period, and the previously established prevalence of MS in Belo Horizonte.

RESULTS

During the study period, there were 69 patients with NMOSD, 60 (87.0%) of whom were females, and 44 (63.8%) non-whites. The median age at disease onset was 36.7 (4-72) years, the mean EDSS score 4.78±2.36, and the mean ARR 0.57±0.43. Anti-aquaporin-4 immunoglobulin testing was available for 61 (88.4%) patients, of whom 41 (67.2%) had a positive result. During the same period, 280 MS patients were seen. Considering the local known prevalence rate of MS of 18.1/100,000 inhabitants, the estimated NMOSD prevalence rate in Belo Horizonte was 4.52/100,000 (95% CI 3.72-5.43) inhabitants.

CONCLUSION

The prevalence rate of NMOSD in Belo Horizonte is high as compared with those found in most of the studies reported to date.

Neuromyelitis optica spectrum disorder (NMOSD) presenting as acute transverse myelitis with positive aquaporin 4 antibodies

An 80-year-old, previously healthy patient presents with acute transverse myelitis with sensory level at T8. The MRI scan of the spinal cord showed longitudinal extensive transverse myelitis, and she tested positive for aquaporin 4 antibodies in serum. She received treatment with intravenous and oral steroids, with no improvement and then underwent plasma exchange. She was then started on azathioprine for prevention of relapses, while continuing physiotherapy and occupational therapy. Eventually, she was transferred to a specialised spinal cord centre for long-term rehabilitation.

Neuromyelitis optica spectrum disorders with non opticospinal manifestations as initial symptoms: a long-term observational study

Background

Early stage neuromyelitis optica spectrum disorders (NMOSD) with non-opticospinal manifestations as initial symptoms are easily misdiagnosed; however, data on the full symptom profile are limited. Moreover, the clinical characteristics and long-term outcomes of these patients remain unknown. We sought to analyze the clinical characteristics, imaging features, and long-term outcomes of NMOSD with non-opticospinal manifestations as initial symptoms.

Methods

We retrospectively included relevant patients from our center. Clinical, demographic, magnetic resonance imaging, treatment, and outcome data were compared according to the non-opticospinal vs. opticospinal initial symptoms.

Results

We identified 43 (9.13 %) patients with non-opticospinal initial symptoms among 471 patients with NMOSD. Of these, 88.37 % developed optic neuritis/myelitis during an average follow-up period of 6.33 years. All the non-opticospinal symptoms were brain/brainstem symptoms. Most of the symptoms and associated brain lesions were reversible. These patients had a younger onset age (P < 0.001), lower serum aquaporin-4 (AQP4) antibody titers (P = 0.030), and a lower Expanded Disability Status Scale (EDSS) score at onset (P < 0.001) and follow-up (P = 0.041) than NMOSD patients with opticospinal initial symptoms. In addition, EDSS scores reached 3.0 (indicating moderate disability) later than in patients with opticospinal initial symptoms (P = 0.028).

Conclusions

Patients with NMOSD with non-opticospinal initial symptoms have a younger onset age, lower serum AQP4 antibody titers, and better clinical outcomes.

B Cells and Antibodies as Targets of Therapeutic Intervention in Neuromyelitis Optica Spectrum Disorders

The first description of neuromyelitis optica by Eugène Devic and Fernand Gault dates back to the 19th century, but only the discovery of aquaporin-4 autoantibodies in a major subset of affected patients in 2004 led to a fundamentally revised disease concept: Neuromyelits optica spectrum disorders (NMOSD) are now considered autoantibody-mediated autoimmune diseases, bringing the pivotal pathogenetic role of B cells and plasma cells into focus. Not long ago, there was no approved medication for this deleterious disease and off-label therapies were the only treatment options for affected patients. Within the last years, there has been a tremendous development of novel therapies with diverse treatment strategies: immunosuppression, B cell depletion, complement factor antagonism and interleukin-6 receptor blockage were shown to be effective and promising therapeutic interventions. This has led to the long-expected official approval of eculizumab in 2019 and inebilizumab in 2020. In this article, we review current pathogenetic concepts in NMOSD with a focus on the role of B cells and autoantibodies as major contributors to the propagation of these diseases. Lastly, by highlighting promising experimental and future treatment options, we aim to round up the current state of knowledge on the therapeutic arsenal in NMOSD.

Atypical optic neuritis: An overview

Optic neuritis (ON) refers to conditions that involve inflammation of the optic nerve. Various autoantibodies have been found, which are associated with central nervous system inflammatory disorders and have provided much information about the immune targets and mechanisms that impact the prognosis, treatment, and recurrence of atypical ON. Therefore, neurologists and ophthalmologists together should work to find out clinical, laboratory, and imaging findings that may provide important clues to the etiology of atypical ON and its management. Various biomarkers have been identified to confirm and distinguish atypical optic neuritis from others. The purpose of this review is to present the current scenario of atypical ON and its clinical management.

Eculizumab: A Review in Neuromyelitis Optica Spectrum Disorder

The terminal complement protein (C5) inhibitor eculizumab (Soliris^®) is the first agent to be specifically approved in the EU, USA, Canada and Japan for the treatment of neuromyelitis optica spectrum disorder (NMOSD) in adults who are aquaporin-4 water channel autoantibody (AQP4-IgG) seropositive and (in the EU only) for those with a relapsing course of disease. In the phase III PREVENT trial, eculizumab significantly reduced the risk of adjudicated relapse relative to placebo in patients with AQP4-IgG-seropositive NMOSD, approximately a quarter of whom did not receive concomitant immunosuppressive therapies. The beneficial effect of eculizumab was seen across all patient subgroups analysed and was accompanied by improvements in neurological and functional disability assessments, as well as generic health-related quality of life measures; it was sustained through 4 years of treatment, according to combined data from the PREVENT trial and an interim analysis of its ongoing open-label extension study. The safety profile of eculizumab in AQP4-IgG-seropositive NMOSD was consistent with that seen for the drug in other approved indications. Thus, eculizumab provides an effective, generally well tolerated and approved treatment option for this rare, disabling and potentially life-threatening condition.

MOG-IgG-associated disorder and systemic lupus erythematosus disease: Systematic review

INTRODUCTION

Myelin oligodendrocyte glycoprotein (MOG) is a nervous system protein expressed by oligodendrocytes to constitute the myelin sheath. Autoantibodies against MOG have been widely described in neurological and autoimmune diseases such as MOG-IgG-associated disorder (MOGAD).Although underlying mechanisms have not yet been understood, an overlap of MOGAD and Systemic Lupus Erythematosus (SLE) has been shown in the literature.

OBJECTIVES

The aim of this systematic review was to assess the possible correlations between MOGAD and SLE based on reported features found in the literature that support the association of the two.

METHODS

A keyword-based literature search was conducted, applying a ten-year filter and using the following key-words: "MOG autoantibody-associated disease and Systemic Lupus Erythematosus"; "MOG and Systemic Lupus Erythematosus" "Anti-MOG and Lupus"; "MOG and SLE"; "MOG and LUPUS" on MEDLINE/PUBMED, ScienceDirect, SciELO, LILACS and Cochrane; and "MOG antibody-associated disease and SLE" on Google Scholar.

RESULTS

Eleven publications reporting on the MOGAD and SLE correlation were included in qualitative synthesis: animal experiment (1), cross-sectional (3), prospective (2), retrospective (1), non-systematic review (3), and case report (1) studies.

CONCLUSION

Not much is known about the connection between MOG-IgG-associated disorder and SLE. Unfortunately, only observational studies have been conducted in humans so far, providing us with limited data. While MOGAD features have been reported to develop in SLE patients, this is not an universal finding. In fact, many different issues impair these results, making it difficult to match the findings of different studies.

Biomarkers in Rare Demyelinating Disease of the Central Nervous System

Rare neurological diseases are a heterogeneous group corresponding approximately to 50% of all rare diseases. Neurologists are among the main specialists involved in their diagnostic investigation. At the moment, a consensus guideline on which neurologists may base clinical suspicion is not available. Moreover, neurologists need guidance with respect to screening investigations that may be performed. In this respect, biomarker research has emerged as a particularly active field due to its potential applications in clinical practice. With respect to autoimmune demyelinating diseases of the Central Nervous System (CNS), although these diseases occur in the frame of organ-specific autoimmunity, pathology of the disease itself is orchestrated among several anatomical and functional compartments. The differential diagnosis is broad and includes, but is not limited to, rare neurological diseases. Multiple Sclerosis (MS) needs to be differentially diagnosed from rare MS variants, Acute Disseminated Encephalomyelitis (ADEM), the range of Neuromyelitis Optica Spectrum Disorders (NMOSDs), Myelin Oligodendrocyte Glycoprotein (MOG) antibody disease and other systemic inflammatory diseases. Diagnostic biomarkers may facilitate timely diagnosis and proper disease management, preventing disease exacerbation due to misdiagnosis and false treatment. In this review, we will describe advances in biomarker research with respect to rare neuroinflammatory disease of the CNS.

Elevated serum interleukin-39 levels in patients with neuromyelitis optica spectrum disorders correlated with disease severity

AIMS

Neuromyelitis optica spectrum disorders (NMOSD) is an inflammatory demyelinating autoimmune disorder in the central nervous system (CNS), which is mainly mediated by aquaporin 4 antibodies (AQP4-Ab). Interleukin (IL)-39 is a new pro-inflammatory cytokine which belongs to the IL-12 cytokine family. However, the role of IL-39 in patients with NMOSD is not completely understood. Therefore, the aim of this study is to explore the possible implication of IL-39 in the pathogenesis of NMOSD.

METHODS

In this study, 50 patients with NMOSD, 20 patients with relapsing-remitting multiple sclerosis (RRMS), 30 patients with non-inflammatory neurological disorders (NND) and 78 healthy controls (HCs) were recruited. The levels of serum IL-39 were measured using the enzyme-linked immunosorbent assay (ELISA).

RESULTS

Our study showed serum IL-39 levels in patients with NMOSD were significantly higher than that in RRMS patients, NND patients and HCs, and positively correlated with Expanded Disability Status Scale (EDSS) score.

CONCLUSION

These findings suggested that IL-39 may play a pro-inflammatory role in the pathogenesis of NMOSD and correlate with disease severity.

Neuromyelitis optica spectrum disorder after presumed coronavirus (COVID-19) infection: A case report

Neuromyelitis optica spectrum disorder is an inflammatory autoimmune condition, predominantly affecting the optic nerves and spinal cord. It has been stated that viral infections play a role in the development of neuromyelitis optica. Several murine coronaviruses can cause inflammatory demyelinating diseases, including optic neuritis. Here we report, to the best of our knowledge, the first human case linking a presumed SARS-CoV-2 infection to the development of NMOSD.

Differential Effects of MS Therapeutics on B Cells-Implications for Their Use and Failure in AQP4-Positive NMOSD Patients

B cells are considered major contributors to multiple sclerosis (MS) pathophysiology. While lately approved disease-modifying drugs like ocrelizumab deplete B cells directly, most MS medications were not primarily designed to target B cells. Here, we review the current understanding how approved MS medications affect peripheral B lymphocytes in humans. These highly contrasting effects are of substantial importance when considering these drugs as therapy for neuromyelitis optica spectrum disorders (NMOSD), a frequent differential diagnosis to MS, which is considered being a primarily B cell- and antibody-driven diseases. Data indicates that MS medications, which deplete B cells or induce an anti-inflammatory phenotype of the remaining ones, were effective and safe in aquaporin-4 antibody positive NMOSD. In contrast, drugs such as natalizumab and interferon-β, which lead to activation and accumulation of B cells in the peripheral blood, lack efficacy or even induce catastrophic disease activity in NMOSD. Hence, we conclude that the differential effect of MS drugs on B cells is one potential parameter determining the therapeutic efficacy or failure in antibody-dependent diseases like seropositive NMOSD.

A tearfully painful darkness

A 70-year-old woman presented with new onset of left eye and facial pain. Ophthalmic and neurological examinations, magnetic resonance imaging brain, erythrocyte sedimentation rate, and C-reactive protein were unrevealing. A few days later, she developed vision loss in her left eye. Examination revealed decreased visual acuity with a relative afferent pupillary defect in the left eye and a diffuse mild swelling of the left optic nerve head. Repeat magnetic resonance imaging showed T2 hyperintensity and enhancement of the intraorbital optic nerve and surrounding tissues with no other intracranial abnormalities. Serum studies showed elevated myelin oligodendrocyte glycoprotein IgG titer. She was treated with IV methylprednisolone 1000 mg daily for 3 days and was discharged on prolonged prednisone taper with return of vision to baseline.

Pre-pregnancy, obstetric and delivery status in women with neuromyelitis optica spectrum disorder

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a potentially disabling disease which affects predominantly women of reproductive age.

OBJECTIVES

To evaluate the pre-pregnancy condition and to investigate the prevalence of obstetrical and neonatal complaints in NMOSD.

METHODS

An observational retrospective study of 37 NMOSD patients positive for aquaporin-4-immunoglobulin-IgG. Age at menarche, menstrual cycle, gravidity, type of delivery obstetrical complications and perinatal problems were recorded. We assessed the annualized relapse rate (ARR).

RESULTS

A total of 23 patients (62%) suffered from irregular menstruations and two from infertility after disease onset. 11 patients had 20 informative pregnancies with 14 deliveries (5 cesareans) and six abortions, four spontaneous, and two ectopic pregnancies after the first trimester. Additionally, three patients experienced threatening abortion and one preeclampsia. No stillbirth or premature birth was recorded. None of the patients experienced attacks during pregnancy, but postpartum relapses occurred after 10 deliveries (71,4%) with the highest ARR (0.937; p = 0.037) during the first three months postpartum compared to pre-pregnancy ARR (0.375). Four patients (10.8%) developed the initial symptoms of NMOSD postpartum.

CONCLUSION

Irregular menstruation in more than half of NMOSD patients may reflect a hormonal imbalance. Pregnancies were associated with obstetrical complications and increased disease activity postpartum.