Intravenous immunoglobulin may reduce relapse frequency in neuromyelitis optica

Intravenous cyclophosphamide and immunoglobulin ameliorated visual field defects in a patient with eosinophilic granulomatosis with polyangiitis

Treating ocular involvement in eosinophilic granulomatosis with polyangiitis (EGPA) can be challenging. We present the case of a 37-year-old woman with EGPA who had severe bilateral visual field defects. Laboratory results showed leukocytosis (17,500 WBC/μL, 25.8 % eosinophils), negative MPO-ANCA titer, and elevated PR3-ANCA level (33.2 IU/mL). Diffusion-weighted MRI revealed bilateral hyperintense occipital lesions, which were more prominent on the left. Her therapy initially included a steroid pulse, followed by daily prednisolone, but her visual field defects remained refractory. The addition of intravenous cyclophosphamide (5 courses) and intravenous immunoglobulin decreased her optic neuropathy and resolved her visual field defects.

Update on the diagnosis and treatment of neuromyelitis optica spectrum disorders (NMOSD) - revised recommendations of the Neuromyelitis Optica Study Group (NEMOS). Part II: Attack therapy and long-term management

This manuscript presents practical recommendations for managing acute attacks and implementing preventive immunotherapies for neuromyelitis optica spectrum disorders (NMOSD), a rare autoimmune disease that causes severe inflammation in the central nervous system (CNS), primarily affecting the optic nerves, spinal cord, and brainstem. The pillars of NMOSD therapy are attack treatment and attack prevention to minimize the accrual of neurological disability. Aquaporin-4 immunoglobulin G antibodies (AQP4-IgG) are a diagnostic marker of the disease and play a significant role in its pathogenicity. Recent advances in understanding NMOSD have led to the development of new therapies and the completion of randomized controlled trials. Four preventive immunotherapies have now been approved for AQP4-IgG-positive NMOSD in many regions of the world: eculizumab, ravulizumab - most recently-, inebilizumab, and satralizumab. These new drugs may potentially substitute rituximab and classical immunosuppressive therapies, which were as yet the mainstay of treatment for both, AQP4-IgG-positive and -negative NMOSD. Here, the Neuromyelitis Optica Study Group (NEMOS) provides an overview of the current state of knowledge on NMOSD treatments and offers statements and practical recommendations on the therapy management and use of all available immunotherapies for this disease. Unmet needs and AQP4-IgG-negative NMOSD are also discussed. The recommendations were developed using a Delphi-based consensus method among the core author group and at expert discussions at NEMOS meetings.

Case report: Use of granulocyte-colony stimulating factor as an immunomodulatory therapy in a patient with neuromyelitis optica spectrum disorder and comorbid immunodeficiency

Background

Autoimmune diseases can coexist with immunodeficiency. We describe a treatment approach in which granulocyte-colony stimulating factor (G-CSF) is used to restore immune competence without worsening autoimmunity. G-CSF is a polyfunctional cytokine that influences survival, proliferation, and differentiation of hematopoietic stem cells, and has immunomodulatory effects on the innate and adaptive immune systems.

Objective

To report a case of neuromyelitis optica spectrum disorder (NMOSD) with comorbid immunodeficiency and frequent infections.

Methods

Case report and review of literature.

Results

A 23 years-old man presented with a focal onset seizure with impaired awareness at age 12. At age 18, he developed headaches, recurrent multifocal seizures, and non-convulsive status epilepticus. Brain magnetic resonance imaging (MRI) showed extensive T2 hyperintense and gadolinium-enhancing periventricular and corpus callosum lesions. Serum aquaporin 4 antibody was positive 1:10,000 (normal value <1.5 titer), hence he was diagnosed with NMOSD. As a complication, patient developed mucormycotic pneumonia with cavitation, requiring thoracotomy precluding use of immunosuppressants. Gene testing demonstrated a mutation in MT-ND4 gene encoding for NADH dehydrogenase 4 in mitochondrial complex 1. Eventually, he began a treatment with filgrastim, a G-CSF analog, in addition to intravenous immunoglobulins and prednisone. Patient's NMOSD has been in remission without relapses, or coexistent infections ever since.

Conclusion

G-CSF is a polyfunctional cytokine with important immunomodulatory effects, which makes it an interesting therapeutic option when autoimmunity coexists with immunodeficiency and was used successfully in this case.

An update on biologic treatments for neuromyelitis optica spectrum disorder

INTRODUCTION

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disease of the central nervous system mediated by antibodies targeting the aquaporin-4 (AQP4) water channel expressed on astrocytes. The binding of specific antibodies to AQP4 causes complement-dependent cytotoxicity, leading to inflammation and demyelination. Several recent phase 2 and 3 randomized placebo-controlled trials showed the efficacy and safety of monoclonal antibody therapies targeting B-cells, interleukin-6 receptor, and complement.

AREAS COVERED

Current biologic treatments for NMOSD and developments therein, and unresolved issues in NMOSD treatment.

EXPERT OPINION

New biologic treatments demonstrate high efficacy and good safety for patients with AQP4-IgG-positive NMOSD. The optimal therapeutics for seronegative NMOSD, pediatric patients, and female patients who are pregnant or wish to be are unclear, and further research is needed. Also, real-world studies of new biological agents and the data on the durability of their beneficial effects and their long-term safety are required. Effective rescue therapy for an acute attack is critical given permanent disability in NMOSD is attack-related, and biologic agents that treat acute attack are emerging. If such treatments are to become widely applied, studies on the most cost-effective treatment strategies are needed.

Update on glial antibody-mediated optic neuritis

Optic neuritis (ON) refers to inflammatory demyelinating lesions of the optic nerve, which can cause acute or subacute vision loss and is a major cause of vision loss in young adults. Much of our understanding of typical ON is from the Optic Neuritis Treatment Trial. Glial autoantibodies to aquaporin-4 immunoglobulin (AQP4-IgG) and myelin oligodendrocyte glycoprotein immunoglobulin (MOG-IgG) are recently established biomarkers of ON that have revolutionized our understanding of atypical ON. The detection of glial antibodies is helpful in the diagnosis, treatment, and follow-up of patients with different types of ON. AQP4-IgG and MOG-IgG screening is strongly recommended for patients with atypical ON. Research on the pathogenesis of NMOSD and MOGAD will promote the development and marketing of targeted immunotherapies. The application of new and efficient drugs, such as the selective complement C5 inhibitor, IL-6 receptor inhibitor, B cell-depleting agents, and drugs against other monoclonal antibodies, provides additional medical evidence. This review provides information on the diagnosis and management of glial antibody-mediated ON.

Effectiveness and tolerability of different therapies in preventive treatment of MOG-IgG-associated disorder: A network meta-analysis

Background

Immunotherapy has been shown to reduce relapses in patients with myelin oligodendrocyte glycoprotein antibody-associated disorder (MOG-AD); however, the superiority of specific treatments remains unclear.

Aim

To identify the efficacy and tolerability of different treatments for MOG-AD.

Methods

Systematic search in Pubmed, Embase, Web of Science, and Cochrane Library databases from inception to March 1, 2021, were performed. Published articles including patients with MOG-AD and reporting the efficacy or tolerability of two or more types of treatment in preventing relapses were included. Reported outcomes including incidence of relapse, annualized relapse rate (ARR), and side effects were extracted. Network meta-analysis with a random-effect model within a Bayesian framework was conducted. Between group comparisons were estimated using Odds ratio (OR) or mean difference (MD) with 95% credible intervals (CrI).

Results

Twelve studies that compared the efficacy of 10 different treatments in preventing MOG-AD relapse, including 735 patients, were analyzed. In terms of incidence of relapse, intravenous immunoglobulins (IVIG), oral corticosteroids (OC), mycophenolate mofetil (MMF), azathioprine (AZA), and rituximab (RTX) were all significantly more effective than no treatment (ORs ranged from 0.075 to 0.34). On the contrary, disease-modifying therapy (DMT) (OR=1.3, 95% CrI: 0.31 to 5.0) and tacrolimus (TAC) (OR=5.9, 95% CrI: 0.19 to 310) would increase the incidence of relapse. Compared with DMT, IVIG significantly reduced the ARR (MD=−0.85, 95% CrI: −1.7 to −0.098). AZA, MMF, OC and RTX showed a trend to decrease ARR, but those results did not reach significant differences. The combined results for relapse rate and adverse events, as well as ARR and adverse events showed that IVIG and OC were the most effective and tolerable therapies.

Conclusions

Whilst DMT should be avoided, IVIG and OC may be suited as first-line therapies for patients with MOG-AD. RTX, MMF, and AZA present suitable alternatives.

Pediatric Neuromyelitis Optica Spectrum Disorder: Case Series and Literature Review

Neuromyelitis Optica Spectrum Disorder (NMOSD) is a central nervous system (CNS) inflammatory demyelinating disease characterized by recurrent inflammatory events that primarily involve optic nerves and the spinal cord, but also affect other regions of the CNS, including hypothalamus, area postrema and periaqueductal gray matter. The aquaporin-4 antibody (AQP4-IgG) is specific for NMOSD. Recently, myelin oligodendrocyte glycoprotein antibodies (MOG-IgG) have been found in a group of AQP4-IgG negative patients. NMOSD is rare among children and adolescents, but early diagnosis is important to start adequate therapy. In this report, we present cases of seven pediatric patients with NMOSD and we review the clinical and neuroimaging characteristics, diagnosis, and treatment of NMOSD in children.

Treatment of Neuromyelitis Optica Spectrum Disorders

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune central nervous system (CNS) inflammatory disorder that can lead to serious disability and mortality. Females are predominantly affected, including those within the reproductive age. Most patients develop relapsing attacks of optic neuritis; longitudinally extensive transverse myelitis; and encephalitis, especially brainstem encephalitis. The majority of NMOSD patients are seropositive for IgG autoantibodies against the water channel protein aquaporin-4 (AQP4-IgG), reflecting underlying aquaporin-4 autoimmunity. Histological findings of the affected CNS tissues of patients from in-vitro and in-vivo studies support that AQP4-IgG is directly pathogenic in NMOSD. It is believed that the binding of AQP4-IgG to CNS aquaporin-4 (abundantly expressed at the endfoot processes of astrocytes) triggers astrocytopathy and neuroinflammation, resulting in acute attacks. These attacks of neuroinflammation can lead to pathologies, including aquaporin-4 loss, astrocytic activation, injury and loss, glutamate excitotoxicity, microglial activation, neuroinflammation, demyelination, and neuronal injury, via both complement-dependent and complement-independent pathophysiological mechanisms. With the increased understanding of these mechanisms underlying this serious autoimmune astrocytopathy, effective treatments for both active attacks and long-term immunosuppression to prevent relapses in NMOSD are increasingly available based on the evidence from retrospective observational data and prospective clinical trials. Knowledge on the indications and potential side effects of these medications are essential for a clear evaluation of the potential benefits and risks to NMOSD patients in a personalized manner. Special issues such as pregnancy and the coexistence of other autoimmune diseases require additional concern and meticulous care. Future directions include the identification of clinically useful biomarkers for the prediction of relapse and monitoring of the therapeutic response, as well as the development of effective medications with minimal side effects, especially opportunistic infections complicated by long-term immunosuppression.

[Treatment of antibody-mediated encephalomyelitis : Strategies for the treatment of neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody-associated disease]

BACKGROUND

Antibody-mediated encephalomyelitis, such as neuromyelitis optica spectrum disorder (NMOSD), myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and glial fibrillary acidic protein (GFAP) antibody-associated astrocytopathy belong to a group of newly described autoimmune diseases.

AIM

Presentation of the treatment of antibody-mediated encephalomyelitis with a focus on NMOSD and MOGAD.

METHODS

Selective literature search in PubMed taking the consultation version of the S2k guidelines of the German Society of Neurology (DGN) on the diagnosis and treatment of multiple sclerosis (MS), NMOSD and MOG IgG-associated diseases into account.

RESULTS

Acute relapses are treated with high-dose steroid pulse therapy or apheresis therapy (plasma exchange or immunoadsorption). It is crucial to start treatment as quickly as possible and apheresis therapy can also be used as first-line treatment under certain conditions. For prophylactic immunotherapy, steroids, classical immunosuppressants and monoclonal antibodies with specific mechanisms of action are used. Eculizumab, inebilizumab and satralizumab are the first drugs approved for NMOSD. Symptomatic treatment and neurorehabilitation are important complementary measures.

CONCLUSION

Treatment of antibody-mediated encephalomyelitis differs from treatment of multiple sclerosis and requires specific measures.

Optimal management of neuromyelitis optica spectrum disorder with aquaporin-4 antibody by oral prednisolone maintenance therapy

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a relapsing neuroinflammatory disease associated with aquaporin-4 antibody. Since disabilities in patients with NMOSD accumulate with attacks, relapse prevention is crucially important for improving long-term outcomes. Corticosteroids are inexpensive and promising drugs for relapse prevention in NMOSD, but few studies have analysed the efficacy of corticosteroids in NMOSD, especially regarding the appropriate dosing and tapering regimens.

METHODS

A single-center, retrospective analysis of corticosteroid therapy in aquaporin-4 antibody-positive NMOSD patients fulfilling the 2015 international consensus diagnostic criteria was conducted.

RESULTS

Medical records of a total of 89 Japanese patients with aquaporin-4 antibody-positive NMOSD seen at Department of Neurology, Tohoku University Hospital (2000~2016) were reviewed. At the last follow-up, 66% of the patients were treated with prednisolone (PSL) monotherapy, and the percentage of those receiving PSL monotherapy or a combination of PSL and other immunosuppressants increased from 17.5% in 2000 to 94.1% in 2016. On the other hand, annualised relapse rate (ARR) decreased from 0.78 (13 attacks in 200 person-months) in 2000 to 0.07 (5 attacks in 819 person-months) in 2016. Under PSL treatment, the mean ARR significantly decreased, and disabilities stabilized (PSL treatment vs no-medication; ARR: 0.21 vs 0.98, P < 0.01, Expanded Disability Status Scale score change: +0.02 vs +0.89, P < 0.01, observation periods: 60.1 vs 68.2 months, P=0.26). Using Kaplan-Meier curves, the 10-year relapse-free rate was 46.5% with PSL monotherapy and 7.1% with no medication (hazard ratio: 0.069, 95% confidence interval [CI] 0.024-0.199, P < 0.01). Rapid tapering of PSL (10 mg or less in one year and/or 5 mg or less in two years after clinical attacks) was associated with frequent relapses compared to gradual tapering (more than 10 mg in one year and more than 5 mg in two years after clinical attacks) (rapid vs gradual, 36.7% vs 17.7%, odds ratio 2.69, 95% CI 1.12-6.44, P = 0.02). However, even with PSL of 5 mg/day or less, the relapse rate was low after two years of acute treatment (before vs after, 53.8% vs 13.6%, odds ratio 0.12, 95% CI 0.03-0.50, P < 0.01). Nine patients needed additional immunosuppressants due to insufficient relapse prevention by PSL monotherapy. PSL monotherapy was generally well tolerated, but seven patients had severe adverse events, mainly bone fractures (5 with bone fracture, 1 with femoral capital necrosis and 1 with cerebral infarction).

CONCLUSION

Our study suggests that PSL monotherapy is effective to prevent relapses in about half of patients with aquaporin-4 antibody-positive NMOSD if the doses are gradually reduced. Although it is important to have a treatment strategy tailored to each patient, this study provides evidence that PSL monotherapy can be an option for relapse prevention in some patients with NMOSD.

Intravenous immunoglobulin treatment for steroid-resistant optic neuritis: a multicenter, double-blind, randomized, controlled phase III study

PURPOSE

To evaluate the efficacy and safety of intravenous "freeze-dried sulfonated human normal immunoglobulin (GGS)" in patients with steroid-resistant optic neuritis (ON).

STUDY DESIGN

Multicenter, prospective, double-blind, parallel-group, randomized controlled trial.

METHODS

Patients with steroid-resistant acute ON were randomly assigned to receive either intravenous GGS (GGS group) or intravenous methylprednisolone (steroid pulse [SP] group). Visual acuity (logarithm of the minimum angle of resolution [logMAR]), mean deviation (MD) value of the Humphrey Field Analyzer, and critical flicker fusion frequency were measured as efficacy endpoints; adverse events (AEs) were assessed as the safety endpoint.

RESULTS

Thirty-two patients (16 patients/group) received the study drugs. The primary endpoint, change in logMAR at week 2 compared to baseline, showed no statistically significant intergroup difference. However, compared with the SP group, change in the GGS group was increasingly indicative of visual improvement, with least squares mean difference of > 0.3 logMAR. On post-hoc analyses, the percentage of patients in the GGS and SP groups with improvement by ≥ 0.3 logMAR at week 2 were 75.0% and 31.3%, respectively. Changes in MD values at week 2 compared to baseline were 9.258  ±  8.296 (mean ± standard deviation) dB and 3.175  ±  6.167 dB in the GGS and SP groups, respectively. These results showed statistically significant intergroup differences (visual acuity improvement, P = 0.032; change in MD values, P = 0.030). No clinically significant AEs were observed.

CONCLUSION

Our results suggest that intravenous immunoglobulin could be a safe and efficacious therapeutic option for prompt treatment of steroid-resistant acute ON.

TRIAL REGISTRATION

JapicCTI-132080.

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.

Predictive Factors of Resistance to High-Dose Steroids Therapy in Acute Attacks of Neuromyelitis Optica Spectrum Disorder

High-dose steroids, the first-line therapy for acute attacks in neuromyelitis optica spectrum disorder (NMOSD), were ineffective in a proportion of NMOSD attacks. This study aimed to explore possible predictors of high-dose steroid resistance. Demographics and disease characteristics of acute attacks were compared between those who responded to high-dose intravenous methylprednisolone (IVMP) and those resistant to IVMP. In total, 197 attacks in 160 patients were identified in our NMOSD registry. Compared with responders, attacks resistant to high-dose steroids tended to have a higher proportion of previous history of immunosuppressive use (25.5 vs. 15.5%, p = 0.080). Significantly higher levels of proteins in the cerebrospinal fluid (CSF) were found in non-responders than in responders [485.5 (388–656) vs. 387 (291.5–532) mg/L, p = 0.006]. More active lesions were found in the brain stem of non-responders (8 attacks in 55, 14.5%), especially in the pons (7.3%) and medulla (14.5%), as opposed to responders (7 patients in 142, 4.9%). Multivariable logistic regression showed that resistance to high-dose steroid treatment was associated with previous immunosuppressant use [odds ratio (OR), 2.31; 95% confidence interval (CI) 1.002–5.34, p = 0.049], CSF protein level above 450 mg/L (OR 3.42, 95% CI 1.72–6.82, p < 0.001), and active lesions in the brainstem (OR 3.80, 95% CI 1.17–12.32, p = 0.026). In conclusion, NMOSD patients with previous use of immunosuppressants, higher levels of CSF protein, and active lesions in the brainstem are more likely to respond poorly to high-dose IVMP alone during an acute attack.

E.U. paediatric MOG consortium consensus: Part 5 - Treatment of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders

In recent years, the understanding about the different clinical phenotypes, diagnostic and prognostic factors of myelin oligodendrocyte glycoprotein-antibody-associated disorders (MOGAD) has significantly increased. However, there is still lack of evidence-based treatment protocols for acute attacks and children with a relapsing course of the disease. Currently used acute and maintenance treatment regimens are derived from other demyelinating central nervous system diseases and are mostly centre-specific. Therefore, this part of the Paediatric European Collaborative Consensus attempts to provide recommendations for acute and maintenance therapy based on clinical experience and evidence available from mainly retrospective studies. In the acute attack, intravenous methylprednisolone (IVMP) leads to a favourable outcome in the majority of patients and can be followed by tapering of oral steroids up to a maximum of three months to maintain the benefit of acute treatment by suppressing disease activity. Intravenous immunoglobulins (IVIG) and plasmapheresis constitute second-line therapies in case of insufficient response to IVMP. After a first relapse, maintenance treatment should be started in order to prevent further relapses and the possibility of permanent sequelae. Four first-line therapies consisting of rituximab (RTX), azathioprine, mycophenolate mofetil or monthly IVIG have been identified by the consensus group. In case of further relapses despite maintenance treatment, the consensus group recommends treatment escalation with RTX or IVIG, followed by combining those two, and ultimately adding maintenance oral steroids. Many open questions remain which need to be addressed in further international prospective evaluation of MOGAD treatment. This international collaboration is essential to expand the state of current knowledge.

Neuromyelitis optica

Neuromyelitis optica (NMO; also known as Devic syndrome) is a clinical syndrome characterized by attacks of acute optic neuritis and transverse myelitis. In most patients, NMO is caused by pathogenetic serum IgG autoantibodies to aquaporin 4 (AQP4), the most abundant water-channel protein in the central nervous system. In a subset of patients negative for AQP4-IgG, pathogenetic serum IgG antibodies to myelin oligodendrocyte glycoprotein, an antigen in the outer myelin sheath of central nervous system neurons, are present. Other causes of NMO (such as paraneoplastic disorders and neurosarcoidosis) are rare. NMO was previously associated with a poor prognosis; however, treatment with steroids and plasma exchange for acute attacks and with immunosuppressants (in particular, B cell-depleting agents) for attack prevention has greatly improved the long-term outcomes. Recently, a number of randomized controlled trials have been completed and the first drugs, all therapeutic monoclonal antibodies, have been approved for the treatment of AQP4-IgG-positive NMO and its formes frustes.

Rapid Administration of High-Dose Intravenous Methylprednisolone Improves Visual Outcomes After Optic Neuritis in Patients With AQP4-IgG-Positive NMOSD

Objective: The purpose of this study was to elucidate the rapid impact of high-dose intravenous methylprednisolone pulse therapy (1,000 mg/day for 3 days) on the eventual visual prognosis in patients with serum anti-aquaporin-4 immunoglobulin G (AQP4-IgG)–positive neuromyelitis optica spectrum disorders (NMOSDs) who had an attack of optic neuritis (ON).

Methods: Data from 32 consecutive NMOSD patients (1 male and 31 female) with at least one ON attack, involving a total of 36 ON-involved eyes, were evaluated. The following variables at ON onset were evaluated: sex, age at the first ON episode, visual acuity at nadir, visual acuity after 1 year, duration from ON onset to treatment for an acute ON attack, cycles of high-dose intravenous methylprednisolone pulse therapy for the ON attack, and cycles of plasmapheresis for the ON attack. Among the 36 ON-involved eyes, 27 eyes were studied using orbital MRI with a short-T1 inversion recovery sequence and gadolinium-enhanced fat-suppressed T1 imaging before starting treatment in the acute phase.

Results: In univariate analyses, a shorter duration from ON onset to the initiation of high-dose intravenous methylprednisolone pulse therapy favorably affected the eventual visual prognosis 1 year later (Spearman's rho = 0.50, p = 0.0018). The lesion length on orbital MRI was also correlated with the eventual visual prognosis (rho = 0.68, p < 0.0001). Meanwhile, the days to steroid pulse therapy and lesion length on orbital MRI did not show a significant correlation. These findings suggest that the rapidness of steroid pulse therapy administration affects the eventual visual prognosis independent of the severity of ON. In multivariate analysis, a shorter time from ON onset to the start of acute treatment (p = 0.0004) and a younger age at onset (p = 0.0071) were significantly associated with better visual outcomes.

Conclusions: Rapid initiation of high-dose intravenous methylprednisolone pulse therapy is essential to preserve the eventual visual acuity in patients with serum AQP4-IgG-positive NMOSD. Once clinicians suspect acute ON with serum AQP4-IgG, swift administration of steroid pulse therapy before confirming the positivity of serum AQP4-IgG would be beneficial for preserving visual function.

Management of Idiopathic CNS inflammatory diseases during the COVID-19 pandemic: Perspectives and strategies for continuity of care from a South East Asian Center with limited resources

The Covid-19 pandemic poses a grave health management challenge globally of unprecedented nature. Management of idiopathic Central Nervous system inflammatory disorders (iCNSID) such as Multiple sclerosis, Neuromyelitis optica and its spectrum disorders and related conditions during this pandemic needs to be addressed with affirmative and sustainable strategies in order to prevent disease related risks, medication related complications and possible COVID-19 disease associated effects. Global international iCNSIDs agencies and recent publications are attempting to address this but such guidance is not available in South East Asia. Here we outline prospectively qualitatively and quantitatively novel strategies at a tertiary center in Malaysia catering for neuroimmunological disorders despite modest resources during this pandemic. In this retrospective study with longitudinal follow-up, we describe stratification of patients for face to face versus virtual visits in the absence of formal teleneurology, stratification of patients for treatment according to disease activity, rescheduling, deferring initiation or extending treatment intervals of certain disease modifying therapies(DMT's) or immunosuppressants(IS), especially those producing lymphocyte depletion in MS and the continuation of IS in patients with NMO/NMOSD. Furthermore, we highlight the use off-label treatments such as Intravenous immunoglobulins/rituximab,bridging interferons/Teriflunomide temporarily replacing more potent DMT choices,supply challenges of IS/DMT's and tailoring blood watches and neuroimaging surveillance based on the current health needs to stave off the pandemic and prevent at risk patients with iCNSID/health care workers from possibly being exposed to the COVID-19.

[Neuromyelitis optica and neuromyelitis optica spectrum disorders]

The review is devoted to up-to-date data on epidemiology, aspects of the pathogenesis of neuromyelitis optica (NMO) and neuromyelitis optica spectrum disorders (NMOSD). The authors consider a role of myelin oligodendrocyte glycoprotein immunoglobulin G (MOG-IgG) in the syndromes phenotypically similar to NMO and NMOSD. Special attention is drawn to the methods of MOG-IgG antibodies detection and indications for testing. The approaches and management for treatment and prevention of NMO relapses, risks of complications during pregnancy and immediately after delivery, as well as methods for their prevention and treatment, are described.

Pediatric NMOSD: A Review and Position Statement on Approach to Work-Up and Diagnosis

Neuromyelitis Optica Spectrum Disorder (NMOSD) is an inflammatory demyelinating disease of the central nervous system (CNS) primarily affecting the optic nerves and spinal cord, but also involving other regions of the CNS including the area postrema, periaqueductal gray matter, and hypothalamus. Knowledge related to pediatric manifestations of NMOSD has grown in recent years, particularly in light of newer information regarding the importance of not only antibodies to aquaporin 4 (AQP4-IgG) but also myelin oligodendrocyte glycoprotein (MOG-IgG) in children manifesting clinically with this syndrome. In this review, we describe the current state of the knowledge related to clinical manifestations, diagnosis, and chronic therapies for children with NMOSD, with emphasis on literature that has been published in the last 5 years. Following the review, we propose recommendations for the assessment/follow up clinical care, and treatment of this population.

Role of complement and potential of complement inhibitors in myasthenia gravis and neuromyelitis optica spectrum disorders: a brief review

The complement system is a powerful member of the innate immune system. It is highly adept at protecting against pathogens, but exists in a delicate balance between its protective functions and overactivity, which can result in autoimmune disease. A cascade of complement proteins that requires sequential activation, and numerous complement regulators, exists to regulate a proportionate response to pathogens. In spite of these mechanisms there is significant evidence for involvement of the complement system in driving the pathogenesis of variety of diseases including neuromyelitis optica spectrum disorders (NMOSD) and myasthenia gravis (MG). As an amplification cascade, there are an abundance of molecular targets that could be utilized for therapeutic intervention. Clinical trials assessing complement pathway inhibition in both these conditions have recently been completed and include the first randomized placebo-controlled trial in NMOSD showing positive results. This review aims to review and update the reader on the complement system and the evolution of complement-based therapeutics in these two disorders.

Efficacy and Tolerability of Intravenous Immunoglobulin and Subcutaneous Immunoglobulin in Neurologic Diseases

PURPOSE

IV immunoglobulin (Ig) therapy has been widely used for the treatment of neurologic disorders, autoimmune diseases, immunodeficiency-related diseases, blood system diseases, and cancers. In this review, we summarize the efficacy and tolerability of IVIg and SCIg therapy in neurologic diseases.

METHODS

We summarized and analyzed the efficacy and tolerability of IVIg and SCIg in neurologic diseases, by analyzing the literature pertaining to the use of IVIg and SCIg to treat nervous system diseases.

FINDINGS

In clinical neurology practice, IVIg has been shown to be useful for the treatment of new-onset or recurrent immune diseases and for long-term maintenance treatment of chronic diseases. Moreover, IVIg may have applications in the management of intractable autoimmune epilepsy, paraneoplastic syndrome, autoimmune encephalitis, and neuromyelitis optica. SCIg is emerging as an alternative to IVIg treatment. Although SCIg has a composition similar to that of IVIg, the applications of this therapy are different. Notably, the bioavailability of SCIg is lower than that of IVIg, but the homeostasis level is more stable. Current studies have shown that these 2 therapies have pharmacodynamic equivalence.

IMPLICATIONS

In this review, we explored the efficacy of IVIg in the treatment of various neurologic disorders. IVIg administration still faces many challenges. Thus, it will be necessary to standardize the use of IVIg in the clinical setting. SCIg administration is a novel and feasible treatment option for neurologic and immune-related diseases, such as chronic inflammatory demyelinating polyradiculoneuropathy and idiopathic inflammatory myopathies. As our understanding of the mechanisms of action of IVIg improve, potential next-generation biologics can being developed.

Neuromyelitis optica spectrum disorders with vertigo as the initial symptom: A case report

RATIONALE

Brain abnormalities have frequently been reported in neuromyelitis optica spectrum disorders patients, but vertigo as an initial manifestation has rarely been described.

PATIENT CONCERNS

A 64-year-old woman who initially presented with vertigo, then accompanied with other brainstem manifestations and spinal cord involvement.

DIAGNOSES

MRI revealed medulla oblongata, cervical and thoracic spinal cord lesions. NMO-IgG antibody was seropositive. Taken her previous medical history and clinical manifestations into consideration, the patient was eventually diagnosed as neuromyelitis optica spectrum disorders.

INTERVENTIONS

Before diagnosis, symptomatic treatment and acupuncture were adopted, whereas after diagnosis, steroid, intravenous immunoglobulin, and immunosuppressant were supplemented.

OUTCOMES

Her dizziness, nausea and vomiting were gradually relieved by symptomatic treatment and acupuncture before the confirmed diagnosis and immunotherapy. After added treatment with steroid, immunosuppressant, especially intravenous immunoglobulin, diplopia and nystagmus disappeared, and superficial sensation was improving. She was fully recovered six months after admission.

LESSONS

Vertigo as a rare prodrome of neuromyelitis optica spectrum disorders deserves attention. The symptoms and signs were improved by a combined treatment of steroid, immunosuppressant, acupuncture, and particularly intravenous immunoglobulin.

Successful intravenous immunoglobulin treatment in relapsing MOG-antibody-associated disease

Treatment of MOG Ab-associated disease is poorly standardized: several drugs have been employed, with variable results. A 50-year-old Caucasian male was admitted to hospital in 2009, with severe acute transverse myelitis. A brain and spinal cord MRI showed multiple demyelinating lesions and cerebrospinal fluid analysis revealed no oligoclonal bands (OCBs). A diagnosis of multiple sclerosis (MS) was made. He was treated with interferon-beta 1a, then with fingolimod, and finally with rituximab. All these treatments were ineffective: he experienced several spinal and brainstem relapses, with residual disability. Finally, an empirical therapy with IVIg was started. Calling into question the diagnosis of MS, we performed anti-MOG test (positive). IVIg therapy was continued and the patient experienced only one mild relapse during a 24-month follow-up. Our patient, with an aggressive and atypical MOG Ab-associated disease, showed a very good response to longterm IVIg treatment.

Diagnosis and Treatment of NMO Spectrum Disorder and MOG-Encephalomyelitis

Neuromyelitis optica spectrum disorders (NMOSD) are autoantibody mediated chronic inflammatory diseases. Serum antibodies (Abs) against the aquaporin-4 water channel lead to recurrent attacks of optic neuritis, myelitis and/or brainstem syndromes. In some patients with symptoms of NMOSD, no AQP4-Abs but Abs against myelin-oligodendrocyte-glycoprotein (MOG) are detectable. These clinical syndromes are now frequently referred to as "MOG-encephalomyelitis" (MOG-EM). Here we give an overview on current recommendations concerning diagnosis of NMOSD and MOG-EM. These include antibody and further laboratory testing, MR imaging and optical coherence tomography. We discuss therapeutic options of acute attacks as well as longterm immunosuppressive treatment, including azathioprine, rituximab, and immunoglobulins.

Recombinant IgG1 Fc hexamers block cytotoxicity and pathological changes in experimental in vitro and rat models of neuromyelitis optica

Intravenous human immunoglobulin G (IVIG) may have therapeutic benefit in neuromyelitis optica spectrum disorders (herein called NMO), in part because of the anti-inflammatory properties of the IgG Fc region. Here, we evaluated recombinant Fc hexamers consisting of the IgM μ-tailpiece fused with the Fc region of human IgG1. In vitro, the Fc hexamers prevented cytotoxicity in aquaporin-4 (AQP4) expressing cells and in rat spinal cord slice cultures exposed to NMO anti-AQP4 autoantibody (AQP4-IgG) and complement, with >500-fold greater potency than IVIG or monomeric Fc fragments. Fc hexamers at low concentration also prevented antibody-dependent cellular cytotoxicity produced by AQP4-IgG and natural killer cells. Serum from rats administered a single intravenous dose of Fc hexamers at 50 mg/kg taken at 8 h did not produce complement-dependent cytotoxicity when added to AQP4-IgG-treated AQP4-expressing cell cultures. In an experimental rat model of NMO produced by intracerebral injection of AQP4-IgG, Fc hexamers at 50 mg/kg administered before and at 12 h after AQP4-IgG fully prevented astrocyte injury, complement activation, inflammation and demyelination. These results support the potential therapeutic utility of recombinant IgG1 Fc hexamers in AQP4-IgG seropositive NMO.

Efficacy of Polyvalent Human Immunoglobulins in an Animal Model of Neuromyelitis Optica Evoked by Intrathecal Anti-Aquaporin 4 Antibodies

Neuromyelitis Optica Spectrum Disorders (NMOSD) are associated with autoantibodies (ABs) targeting the astrocytic aquaporin-4 water channels (AQP4-ABs). These ABs have a direct pathogenic role by initiating a variety of immunological and inflammatory processes in the course of disease. In a recently-established animal model, chronic intrathecal passive-transfer of immunoglobulin G from NMOSD patients (NMO-IgG), or of recombinant human AQP4-ABs (rAB-AQP4), provided evidence for complementary and immune-cell independent effects of AQP4-ABs. Utilizing this animal model, we here tested the effects of systemically and intrathecally applied pooled human immunoglobulins (IVIg) using a preventive and a therapeutic paradigm. In NMO-IgG animals, prophylactic application of systemic IVIg led to a reduced median disease score of 2.4 on a 0-10 scale, in comparison to 4.1 with sham treatment. Therapeutic IVIg, applied systemically after the 10th intrathecal NMO-IgG injection, significantly reduced the disease score by 0.8. Intrathecal IVIg application induced a beneficial effect in animals with NMO-IgG (median score IVIg 1.6 vs. sham 3.7) or with rAB-AQP4 (median score IVIg 2.0 vs. sham 3.7). We here provide evidence that treatment with IVIg ameliorates disease symptoms in this passive-transfer model, in analogy to former studies investigating passive-transfer animal models of other antibody-mediated disorders.