Outcome prediction models in AQP4-IgG positive neuromyelitis optica spectrum disorders

Pathogenic antibodies targeting the aquaporin-4 water channel on astrocytes are associated with relapsing inflammatory neuromyelitis optica spectrum disorders. The clinical phenotype is characterized by recurrent episodes of optic neuritis, longitudinally extensive transverse myelitis, area postrema attacks and less common brainstem and cerebral events. Patients often develop major residual disability from these attacks, so early diagnosis and initiation of attackpreventing medications is important. Accurate prediction of relapse would assist physicians in counselling patients, planning treatment and designing clinical trials. We used a large multicentre dataset of 441 patients from the UK, USA, Japan and Martinique who collectively experienced 1976 attacks, and applied sophisticated mathematical modelling to predict likelihood of relapse and disability at different time points. We found that Japanese patients had a lower risk of subsequent attacks except for brainstem and cerebral events, with an overall relative relapse risk of 0.681 (P = 0.001) compared to Caucasians and African patients, who had a higher likelihood of cerebral attacks, with a relative relapse risk of 3.309 (P = 0.009) compared to Caucasians. Female patients had a higher chance of relapse than male patients (P = 0.009), and patients with younger age of onset were more likely to have optic neuritis relapses (P < 0.001). Immunosuppressant drugs reduced and multiple sclerosis disease-modifying agents increased the likelihood of relapse (P < 0.001). Patients with optic neuritis at onset were more likely to develop blindness (P < 0.001), and those with older age of onset were more likely to develop ambulatory disability. Only 25% of long-term disability was related to initial onset attack, indicating the importance of early attack prevention. With respect to selection of patients for clinical trial design, there would be no gain in power by selecting recent onset patients and only a small gain by selecting patients with recent high disease activity. We provide risk estimates of relapse and disability for patients diagnosed and treated with immunosuppressive treatments over the subsequent 2, 3, 5 and 10 years according to type of attack at onset or the first 2-year course, ethnicity, sex and onset age. This study supports significant effects of onset age, onset phenotype and ethnicity on neuromyelitis optica spectrum disorders outcomes. Our results suggest that powering clinical treatment trials based upon relapse activity in the preceding 2 years may offer little benefit in the way of attack risk yet severely hamper clinical trial success.

Short segment myelitis as the initial and only manifestation of aquaporin-4 immunoglobulin G-positive neuromyelitis optica spectrum disorders

Background:

Short segment myelitis (SSM, < 3 vertebral segments) is an under-recognized initial manifestation of neuromyelitis optica spectrum disorders (NMOSD). Though infrequent, failure to recognize SSM in patients with NMOSD would lead to incorrect diagnosis and treatment. Therefore, delineation of features of NMOSD-associated SSM is of paramount importance.

Objective:

Our study aimed to determine the demographic, clinical and radiological features of NMOSD-associated SSM, and compare those with NMOSD-associated longitudinally extensive transverse myelitis (LETM) and multiple sclerosis (MS)-associated SSM, respectively.

Methods:

Chinese patients presenting initially only with acute myelitis and diagnosed with NMOSD (n = 46) and MS (n = 11) were included. Clinical, serological, imaging and disability data were collected. Mann–Whitney U test or two-tailed Fisher’s exact tests were used to analyse the data.

Results:

Of the 46 enrolled NMOSD patients, 34 (74%) collectively had 38 LETM lesions, while 12 (26%) had 14 SSM lesions. When compared with LETM, NMOSD presenting with SSM were more likely to have a delayed diagnosis and a lower level of disability at nadir during the first attack. T1-weighted imaging hypointensity was more prominent in NMOSD-associated LETM lesions than NMOSD-associated SSM lesions. When compared with MS-associated SSM, NMOSD-associated SSM lesions were more likely to be centrally located, grey matter involving and transversally extensive on axial imaging and spanned no less than 2 vertebral segments on sagittal imaging.

Conclusion:

These findings suggest that SSM does not preclude the possibility of a NMOSD diagnosis. Testing for serum aquaporin-4 immunoglobulin G (AQP4-IgG) and careful study of lesions on spinal cord magnetic resonance imaging could aid in an earlier and correct diagnosis.

Alterations in the Brain Structure and Functional Connectivity in Aquaporin-4 Antibody-Positive Neuromyelitis Optica Spectrum Disorder

Purpose

To investigate the mechanisms underlying the gray matter volume (GMV) and functional connectivity (FC) changes in aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (NMOSD) patients.

Methods

This cross-sectional study consisted of 21 patients with aquaporin-4 antibody-positive NMOSD and 22 age- and sex-matched healthy controls. All participants underwent cerebral magnetic resonance imaging and testing each individual’s visual acuity was done.

Results

Neuromyelitis optica spectrum disorder patients showed significantly reduced GMV in the left calcarine, left thalamus and right lingual gyrus of the NMOSD patients when compared to HC (P < 0.05). NMOSD patients showed significantly decreased FC values (P < 0.05) in both the left and right calcarine, right lingual gyrus and left thalamus, respectively, when compared to HC. We also observed a positive correlation between the FC values of the left thalamus, bilateral calcarine gyrus and the visual acuity, respectively (P < 0.05). Furthermore, a negative association was seen between the duration of the disease, frequency of optic neuritis, and the FC values in the lingual gyrus, bilateral calcarine gyrus, and right lingual gyrus, respectively (P < 0.05).

Conclusion

Reduced visual acuity and frequency of optic neuritis are associated with alterations in the GMV and FC in NMOSD. Our current study, which provides imaging evidence on the impairment involved in NMOSD, sheds light on pathophysiological responses of optic neuritis attack on the brain especially on the visual network.

Neuromyelitis optica spectrum disorders in the Arabian Gulf: challenges and growing experience

Neuromyelitis optica spectrum disorders (NMOSD) have been studied in different ethnic groups, including Asians, African-Americans, and Caucasians. Demonstrating the clinical features among diverse communities is important to understand the variable disease phenotypes, which will lead to further classification and better clinical management. Testing for antibody against aquaporin-4 (AQP4), the most common target antigen in NMOSD, is not available in many countries and tests use different methods, with variable sensitivity. With negative antibody results, the diagnosis of NMOSD becomes challenging and may affect the outcomes of patients with NMOSD. There are no adequate studies that assess NMOSD cohorts in the Arabian Gulf region, despite the increasing number of diagnosed cases. It is worth assessing NMOSD cohorts in the Arabian Gulf population to study the natural history of disease and to establish an epidemiological background for future perspectives. Various challenges to implement such a mission are outlined, including disease rarity, overlapping presenting symptoms and signs, which posed the issue of mimickers in the differential diagnosis, lack of specialized clinics, absence of highly sensitive testing methods for diagnosis, and the indefinite agreement on the negative AQP4 NMOSD criteria. Collaborative efforts started to take a place among many experts in the region to establish a registry of NMOSD patients for better perception of the disease pattern.

Clinical Features, Gender Differences, Disease Course, and Outcome in Neuromyelitis Optica Spectrum Disorder

Introduction:

Neuromyelitis optica spectrum disorder (NMOSD) is an astrocytopathy with a predilection for the optic nerve, spinal cord, and brainstem. In this ambispective study, we evaluate clinical characteristics, responses to therapy, and disability outcomes in patients with NMOSD.

Methods:

Patients diagnosed as NMOSD and following up for at least 1 year at a tertiary care center in India were recruited. Patient data were collected ambispectively from January 2012 until December 2018.

Results:

A total of 106 patients (29M/77F) with NMOSD were evaluated. The mean age of onset was 29 (±11.6) years. About 77 patients (72.64%) were positive for the AQP4 antibody. Age of onset was higher for those presenting with an opticospinal syndrome (34.2 years) as compared to either isolated longitudinally extensive transverse myelitis (LETM) (30 years) or optic neuritis (ON) (25.3 years). The most common syndrome at onset was LETM in 57 patients (53.77%) followed by ON in 31 patients (29.24%). Azathioprine was the most common immunotherapy (83.96%) prescribed followed by rituximab (7.54%) and mycophenolate mofetil (1.88%). There was a significant decrease in the number of relapses post-azathioprine (P < 0.001). Out of 67 patients with ON, 21 (31.34%) had complete recovery while 17 (25.37%) patients had a severe deficit at a 3-month follow-up. Out of 92 patients with a motor deficit, 49 (53.26%) patients had a partial motor deficit at a 6-month follow-up. The severe visual deficit at baseline and female gender predicted poor visual and motor recovery, respectively.

Conclusion:

This is the largest descriptive study on patients with NMOSD from India. Relapse rates were similar irrespective of the clinical presentation, age, gender, and disease course. Treatment with immunosuppressive treatment significantly affected the disease course.

Neuroinflammatory and Demyelinating Disorders of Childhood

In this chapter, we will review monophasic and recurrent demyelinating disorders in children. We will first review consensus definitions and provide an approach to the evaluation of children with first episode of acquired demyelinating disorder. We will discuss typical clinical and radiological features of these syndromes. In the second section, we will review features of recurrent demyelinating syndromes in children, focusing on clinical presentation and treatment options.

Free thyroxine level is associated with both relapse rate and poor neurofunction in first-attack Neuromyelitis Optica Spectrum Disorder (NMOSD) patients

Background

To investigate whether the serum free thyroxine (FT4) level is a prognostic factor for the first-attack neuromyelitis optica spectrum disorders (NMOSD).

Methods

This retrospective study enrolled 109 patients with first-attack NMOSD. The Expanded Disability Status Scale (EDSS) and the relapse rate were used to evaluate the outcomes. The logistic regression model was used to analyze the independent effects of FT4 on relapse and final EDSS. Kaplan-Meier analysis, scatter plot smoothing method, and two-phase piecewise linear regression model were used to investigate the relationship between the FT4 level and the relapse rate.

Results

Multivariate analysis revealed that serum FT4 level might be a risk factor for both final EDSS (β = 0.17; 95% confidence interval: 0.03–0.32) and the relapse rate (HR = 1.18; 95% confidence interval: 1.05–1.32). Furthermore, 1400 days after the onset, nearly 100% of patients in the high-FT4 group relapsed, while only 40% of the patients in the low-FT4 group relapsed. Finally, we found that the relationship between the FT4 level and the NMOSD relapse rate was nonlinear. The risk of NMOSD relapse increased with the FT4 level up to the inflection point of 12.01 pmol/L (HR = 1.45; 95% confidence interval: 1.06–1.98). When the FT4 level was > 12.01 pmol/L, there was no correlation between the FT4 level and the risk of NMOSD relapse (HR = 1.05; 95% confidence interval: 0.78–1.41).

Conclusion

Serum FT4 level may be a prognostic indicator for the first-attack in patients with NMOSD. High FT4 levels are associated with poor neurofunctions and a high relapse rate in patients with the first-attack in patients with NMOSD.

Trial of Satralizumab in Neuromyelitis Optica Spectrum Disorder

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disease of the central nervous system and is associated with autoantibodies to anti-aquaporin-4 (AQP4-IgG) in approximately two thirds of patients. Interleukin-6 is involved in the pathogenesis of the disorder. Satralizumab is a humanized monoclonal antibody targeting the interleukin-6 receptor. The efficacy of satralizumab added to immunosuppressant treatment in patients with NMOSD is unclear.

METHODS

In a phase 3, randomized, double-blind, placebo-controlled trial, we randomly assigned, in a 1:1 ratio, patients with NMOSD who were seropositive or seronegative for AQP4-IgG to receive either satralizumab, at a dose of 120 mg, or placebo, administered subcutaneously at weeks 0, 2, and 4 and every 4 weeks thereafter, added to stable immunosuppressant treatment. The primary end point was the first protocol-defined relapse in a time-to-event analysis. Key secondary end points were the change from baseline to week 24 in the visual-analogue scale (VAS) pain score (range, 0 to 100, with higher scores indicating more pain) and the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) score (range, 0 to 52, with lower scores indicating more fatigue). Safety was also assessed.

RESULTS

A total of 83 patients were enrolled, with 41 assigned to the satralizumab group and 42 to the placebo group. The median treatment duration with satralizumab in the double-blind period was 107.4 weeks. Relapse occurred in 8 patients (20%) receiving satralizumab and in 18 (43%) receiving placebo (hazard ratio, 0.38; 95% confidence interval [CI], 0.16 to 0.88). Multiple imputation for censored data resulted in hazard ratios ranging from 0.34 to 0.44 (with corresponding P values of 0.01 to 0.04). Among 55 AQP4-IgG-seropositive patients, relapse occurred in 11% of those in the satralizumab group and in 43% of those in the placebo group (hazard ratio, 0.21; 95% CI, 0.06 to 0.75); among 28 AQP4-IgG-seronegative patients, relapse occurred in 36% and 43%, respectively (hazard ratio, 0.66; 95% CI, 0.20 to 2.24). The between-group difference in the change in the mean VAS pain score was 4.08 (95% CI, -8.44 to 16.61); the between-group difference in the change in the mean FACIT-F score was -3.10 (95% CI, -8.38 to 2.18). The rates of serious adverse events and infections did not differ between groups.

CONCLUSIONS

Among patients with NMOSD, satralizumab added to immunosuppressant treatment led to a lower risk of relapse than placebo but did not differ from placebo in its effect on pain or fatigue. (Funded by Chugai Pharmaceutical; ClinicalTrials.gov number, NCT02028884.).

Prognostic Factors for Recovery of Vision in Canine Optic Neuritis of Unknown Etiology: 26 Dogs (2003-2018)

Optic neuritis (ON) is a recognized condition, yet factors influencing recovery of vision are currently unknown. The purpose of this study was to identify prognostic factors for recovery of vision in canine ON of unknown etiology. Clinical databases of three referral hospitals were searched for dogs with presumptive ON based on clinicopathologic, MRI/CT, and fundoscopic findings. Twenty-six dogs diagnosed with presumptive ON of unknown etiology, isolated (I-ON) and MUE-associated (MUE-ON), were included in the study. Their medical records were reviewed retrospectively, and the association of complete recovery of vision with signalment, clinicopathologic findings, and treatment was investigated. Datasets were tested for normality using the D'Agostino and Shapiro-Wilk tests. Individual datasets were compared using the Chi-squared test, Fisher's exact test, and the Mann-Whitney U-test. For multiple comparisons with parametric datasets, the one-way analysis of variance (ANOVA) was performed, and for non-parametric datasets, the Kruskal-Wallis test was performed to test for independence. For all data, averages are expressed as median with interquartile range and significance set at p < 0.05. Twenty-six dogs met the inclusion criteria. Median follow-up was 230 days (range 21–1901 days, mean 496 days). Six dogs (23%) achieved complete recovery and 20 dogs (77%) incomplete or no recovery of vision. The presence of a reactive pupillary light reflex (p = 0.013), the absence of fundoscopic lesions (p = 0.0006), a younger age (p = 0.038), and a lower cerebrospinal fluid (CSF) total nucleated cell count (TNCC) (p = 0.022) were statistically associated with complete recovery of vision. Dogs with I-ON were significantly younger (p = 0.046) and had lower CSF TNCC (p = 0.030) compared to the MUE-ON group. This study identified prognostic factors that may influence complete recovery of vision in dogs with ON. A larger cohort of dogs is required to determine whether these findings are robust and whether additional parameters aid accurate prognosis for recovery of vision in canine ON.

Neuromyelitis optica spectrum disorders in Arabian Gulf (NMOAG); establishment and initial characterization of a patient registry

OBJECTIVE

To describe the clinical and radiological characteristics of neuromyelitis optica spectrum disorders (NMOSD) patients from the Arabian Gulf relative to anti-aquaporin 4 antibody serostatus.

METHODS

Retrospective multicentre study of hospital records of patients diagnosed with NMOSD based on 2015 International Panel on NMOSD Diagnosis (IPND) consensus criteria.

RESULTS

One hundred forty four patients were evaluated, 64.3% were anti-AQP4 antibody positive. Mean age at onset and disease duration were 31±12 and 7 ± 6 years respectively. Patients were predominantly female (4.7:1). Overall; relapsing course (80%) was more common than monophasic (20%). Optic neuritis was the most frequent presentation (48.6%), regardless of serostatus. The proportion of patients (54.3%) with visual acuity of ≤ 0.1 was higher in the seropositive group (p = 0.018). Primary presenting symptoms of transverse myelitis (TM) were observed in 29% of patients, and were the most significant correlate of hospitalization (p<0.001). Relative to anti-APQ4 serostatus, there were no significant differences in terms of age of onset, course, relapse rates or efficacy outcomes except for oligoclonal bands (OCB), which were more often present in seronegative patients (40% vs.22.5%; p = 0.054). Irrespective of serostatus, several disease modifying therapies were instituted including steroids or immunosuppressives, mostly, rituximab and azathioprine in the cohort irrespective of serostatus. The use of rituximab resulted in reduction in disease activity.

CONCLUSION

This is the first descriptive NMOSD cohort in the Arabian Gulf region. Seropositive patients were more prevalent with female predominance. Relapsing course was more common than monophasic. However, anti-AQP4 serostatus did not impact disease duration, relapse rate or therapeutic effectiveness. These findings offer new insights into natural history of NMOSD in patients of the Arabian Gulf and allow comparison with patient populations in different World regions.

Attack-related damage of thalamic nuclei in neuromyelitis optica spectrum disorders

OBJECTIVES

In neuromyelitis optica spectrum disorders (NMOSD) thalamic damage is controversial, but thalamic nuclei were never studied separately. We aimed at assessing volume loss of thalamic nuclei in NMOSD. We hypothesised that only specific nuclei are damaged, by attacks affecting structures from which they receive afferences: the lateral geniculate nucleus (LGN), due to optic neuritis (ON) and the ventral posterior nucleus (VPN), due to myelitis.

METHODS

Thirty-nine patients with aquaporin 4-IgG seropositive NMOSD (age: 50.1±14.1 years, 36 women, 25 with prior ON, 36 with prior myelitis) and 37 healthy controls (age: 47.8 ± 12.5 years, 32 women) were included in this cross-sectional study. Thalamic nuclei were assessed in magnetic resonance images, using a multi-atlas-based approach of automated segmentation. Retinal optical coherence tomography was also performed.

RESULTS

Patients with ON showed smaller LGN volumes (181.6±44.2 mm³) compared with controls (198.3±49.4 mm³; B=-16.97, p=0.004) and to patients without ON (206.1±50 mm³ ; B=-23.74, p=0.001). LGN volume was associated with number of ON episodes (Rho=-0.536, p<0.001), peripapillary retinal nerve fibre layer thickness (B=0.70, p<0.001) and visual function (B=-0.01, p=0.002). Although VPN was not smaller in patients with myelitis (674.3±67.5 mm³) than controls (679.7±68.33; B=-7.36, p=0.594), we found reduced volumes in five patients with combined myelitis and brainstem attacks (B=-76.18, p=0.017). Volumes of entire thalamus and other nuclei were not smaller in patients than controls.

CONCLUSION

These findings suggest attack-related anterograde degeneration rather than diffuse thalamic damage in NMOSD. They also support a potential role of LGN volume as an imaging marker of structural brain damage in these patients.

Association of Visual Impairment in Neuromyelitis Optica Spectrum Disorder With Visual Network Reorganization

Importance

Severe visual impairment is one of the major symptoms in neuromyelitis optica spectrum disorder (NMOSD), but functional network reorganization induced by the diminished sensory input has not been investigated thus far.

Objective

To examine adaptive visual network connectivity changes in NMOSD.

Design, Setting, and Participants

In this cross-sectional study, data were collected from May 1, 2013, through February 31, 2016, from 31 patients with aquaporin-4 antibody-positive NMOSD and 31 age- and sex-matched healthy control individuals at the Department of Neurology and NeuroCure Clinical Research Center at Charité-Universitätsmedizin Berlin, Berlin, Germany.

Main Outcomes and Measures

Visual function (high-contrast visual acuity and contrast sensitivity), optical coherence tomography (peripapillary retinal nerve fiber layer and ganglion cell layer thickness), and resting-state functional magnetic resonance imaging (functional connectivity of large-scale brain networks).

Results

Thirty-one patients with NMOSD (mean [SD] age, 48.2 [13.9] years; 28 women and 3 men) and 31 healthy controls (mean [SD] age, 47.2 [15.3] years; 28 women and 3 men) participated in the study. Patients had a selective and pronounced increase of functional connectivity in the primary and secondary visual networks. Increased primary visual network connectivity correlated with reduced high-contrast visual acuity (r = -0.39, P = .006), reduced low-contrast sensitivity (r = -0.33, P = .03), and more severe retinal damage measured by optical coherence tomography (r = -0.4, P = .01). Furthermore, visual functional connectivity was significantly higher in patients with a history of optic neuritis compared with patients without optic neuritis (mean [SD] regression coefficients, 50.0 [4.3] vs 34.6 [5.6]; P = .04).

Conclusions and Relevance

Impaired visual function and retinal damage are associated with selective reorganization of the visual network in NMOSD. These findings advance the understanding of visual system dysfunction in NMOSD and, more generally, provide insight into pathophysiologic responses of the visual system to impaired visual input.

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.

Late-onset neuromyelitis optica spectrum disorder: The importance of autoantibody serostatus

Objective

To describe the clinical features of late-onset (≥50 years) neuromyelitis optica spectrum disorder (LO-NMOSD), to compare the outcome with that of early-onset (EO-NMOSD), and to identify predictors of disability.

Methods

A retrospective, multicenter study of 238 patients with NMOSD identified by the 2015 criteria. Clinical and immunologic features of patients with LO-NMOSD were compared with those with EO-NMOSD. All patients were evaluated for aquaporin-4 (AQP4-IgG) and myelin oligodendrocyte glycoprotein (MOG-IgG) antibodies.

Results

Sixty-nine (29%) patients had LO-NMOSD. Demographic features, initial disease presentation, annualized relapse rate, and frequency of AQP4-IgG and MOG-IgG did not differ between patients with LO-NMOSD and EO-NMOSD. Among patients with AQP4-IgG or double seronegativity, those with LO-NMOSD had a higher risk to require a cane to walk (hazard ratio [HR], 2.10, 95% CI 1.3–3.54, p = 0.003 for AQP4-IgG, and HR, 13.0, 95% CI 2.8–59.7, p = 0.001, for double seronegative). No differences in outcome were observed between patients with MOG-IgG and LO-NMOSD or EO-NMOSD. Older age at onset (for every 10-year increase, HR 1.63, 95% CI 1.35–1.92 p < 0.001) in NMOSD, and higher disability after the first attack (HR 1.68, 95% CI 1.32–2.14, p < 0.001), and double seronegativity (HR 3.74, 95% CI 1.03–13.6, p = 0.045) in LO-NMOSD were the main independent predictors of worse outcome.

Conclusions

Patients with LO-NMOSD have similar clinical presentation but worse outcome than EO-NMOSD when they are double seronegative or AQP4-IgG positive. Serostatus and residual disability after first attack are the main predictors of LO-NMOSD outcome.

Review: Recent advances in the understanding of the pathophysiology of neuromyelitis optica spectrum disorder

Neuromyelitis optica is an autoimmune inflammatory disorder of the central nervous system that preferentially targets the spinal cord and optic nerve. Following the discovery of circulating antibodies against the astrocytic aquaporin 4 (AQP4) water channel protein, recent studies have expanded our knowledge of the unique complexities of the pathogenesis of neuromyelitis optica and its relationship with the immune response. This review describes and summarizes the recent advances in our understanding of the molecular mechanisms underlying neuromyelitis optica disease pathology and examines their potential as therapeutic targets. Additionally, we update the most recent research by proposing major unanswered questions regarding how peripheral AQP4 antibodies are produced and their entry into the central nervous system, the causes of AQP4-IgG-seronegative disease, why peripheral AQP4-expressing organs are spared from damage, and the impact of this disease on pregnancy.

The clinical spectrum and prognosis of idiopathic acute optic neuritis: A longitudinal study in Southern Finland

BACKGROUND

To analyse in a population-based setting the clinical features, prognostic factors, and seasonality of patients diagnosed with acute idiopathic optic neuritis (ON).

METHODS

Retrospective analysis of ophthalmological records, laboratory parameters, and magnetic resonance imaging (MRI) of patients with symptoms suggestive of ON referred to the Helsinki University Hospital (serving a population of 1.53 million in Southern Finland) were analysed between May 1, 2008 and April 14, 2012.

RESULTS

Of the 291 patients with suspected ON, 184 (63%) were diagnosed with ON (mean age 34 years, 76% females). Intravenous methylprednisolone treatment was administered in 131 (71%) patients. First ON was diagnosed in 123 patients (67%), 55 (30%) had a previous diagnosis of multiple sclerosis (MS) and two patients with their first ON were diagnosed with neuromyelitis optica. Evolution of best corrected visual acuity (BCVA) was analysed in 132 (72%) patients, who were reviewed median of 38 days after onset. Median and mean BCVAs in these reviewed patients were 0.4 and 0.2 at the time of diagnosis and 1.0 and 0.5 at the time of the review. Recovery was relatively good in the majority of patients; 82% (n = 108) had reached BCVA of ≥0.5 and 70% (n = 92) and BCVA of ≥0.8 at the time of the review, while thirteen (10%) had poor prognosis, BCVA ≤0.1 at review. Accessory clinical features included optic disc swelling (21%), colour vision impairment (75%), and pain with eye movements (65%). Relative afferent pupillary defect was abnormal in 76% of the patients with their first ON. Baseline visual acuity was most strongly associated with visual outcome at review (P < 0.001, linear regression). Optic disc swelling and the presence of lesions in the optic nerve on MRI had a more modest association with poorer recovery (P = 0.033 and P = 0.049, respectively), while age, sex, previous history of ON, and previous diagnosis of multiple sclerosis were not associated with outcome at review. Incidence of ON showed a clear seasonal pattern; there were two times more cases in April to June versus October to December (P = 0.03), confirming previous results from Sweden.

CONCLUSIONS

Our data suggest that besides baseline visual acuity, optic disc swelling and lesions in the optic nerve on MRI are associated with poorer prognosis. As in previous studies, we observed that diagnostics of ON is difficult, accessory clinical findings such as pain and RAPD are not always present. Although the diagnosis of ON is clinical, the role of MRI should be considered in differential diagnostics and in defining potential prognostic markers.

Neuromyelitis Optica Spectrum Disorder and Anti-MOG Syndromes

Neuromyelitis optica spectrum disorder (NMOSD) and anti-myelin oligodendrocyte glycoprotein (anti-MOG) syndromes are immune-mediated inflammatory conditions of the central nervous system that frequently involve the optic nerves and the spinal cord. Because of their similar clinical manifestations and habitual relapsing course they are frequently confounded with multiple sclerosis (MS). Early and accurate diagnosis of these distinct conditions is relevant as they have different treatments. Some agents used for MS treatment may be deleterious to NMOSD. NMOSD is frequently associated with antibodies which target aquaporin-4 (AQP4), the most abundant water channel in the CNS, located in the astrocytic processes at the blood-brain barrier (BBB). On the other hand, anti-MOG syndromes result from damage to myelin oligodendrocyte glycoprotein (MOG), expressed on surfaces of oligodendrocytes and myelin sheaths. Acute transverse myelitis with longitudinally extensive lesion on spinal MRI is the most frequent inaugural manifestation of NMOSD, usually followed by optic neuritis. Other core clinical characteristics include area postrema syndrome, brainstem, diencephalic and cerebral symptoms that may be associated with typical MRI abnormalities. Acute disseminated encephalomyelitis and bilateral or recurrent optic neuritis are the most frequent anti-MOG syndromes in children and adults, respectively. Attacks are usually treated with steroids, and relapses prevention with immunosuppressive drugs. Promising emerging therapies for NMOSD include monoclonal antibodies and tolerization.

Cognitive Impairment in Neuromyelitis Optica Spectrum Disorders: A Review of Clinical and Neuroradiological Features

Neuromyelitis optica spectrum disorders (NMOSD) are mostly relapsing autoimmune inflammatory disorders of the central nervous system (CNS) with optic neuritis, myelitis, and brainstem syndromes as clinical hallmarks. With a reported prevalence of up to 70%, cognitive impairment is frequent, but often unrecognized and an insufficiently treated burden of the disease. The most common cognitive dysfunctions are decline in attention and memory performance. Magnetic resonance imaging can be used to access structural correlates of neuropsychological disorders. Cognitive impairment is not only a highly underestimated symptom in patients with NMOSD, but potentially also a clinical correlate of attack-independent changes in NMOSD, which are currently under debate. This article reviews cognitive impairment in NMOSD and discusses associations between structural changes of the CNS and cognitive deficits.

Clinical presentation and prognosis in MOG-antibody disease: a UK study

See de Seze (doi:10.1093/brain/awx292) for a scientific commentary on this article. A condition associated with an autoantibody against MOG has been recently recognized as a new inflammatory disease of the central nervous system, but the disease course and disability outcomes are largely unknown. In this study we investigated clinical characteristics of MOG-antibody disease on a large cohort of patients from the UK. We obtained demographic and clinical data on 252 UK patients positive for serum immunoglobulin G1 MOG antibodies as tested by the Autoimmune Neurology Group in Oxford. Disability outcomes and disease course were analysed in more detail in a cohort followed in the Neuromyelitis Optica Oxford Service (n = 75), and this included an incident cohort who were diagnosed at disease onset (n = 44). MOG-antibody disease affects females (57%) slightly more often than males, shows no ethnic bias and typically presents with isolated optic neuritis (55%, bilateral in almost half), transverse myelitis (18%) or acute disseminated encephalomyelitis-like presentations (18%). In the total Oxford cohort after a median disease duration of 28 months, 47% of patients were left with permanent disability in at least one of the following: 16% patients had visual acuity ≤6/36 in at least one eye, mobility was limited in 7% (i.e. Expanded Disability Status Scale ≥ 4.0), 5% had Expanded Disability Status Scale ≥ 6.0, 28% had permanent bladder issues, 20% had bowel dysfunction, and 21% of males had erectile dysfunction. Transverse myelitis at onset was a significant predictor of long-term disability. In the incident cohort 36% relapsed after median disease duration of 16 months. The annualized relapse rate was 0.2. Immunosuppression longer than 3 months following the onset attack was associated with a lower risk of a second relapse. MOG-antibody disease has a moderate relapse risk, which might be mitigated by medium term immunosuppression at onset. Permanent disability occurs in about half of patients and more often involves sphincter and erectile functions than vision or mobility.

A comparison between spinal cord infarction and neuromyelitis optica spectrum disorders: Clinical and MRI studies

This study aims to investigate the clinical features and magnetic resonance imaging (MRI) findings in patients with spinal cord infarction (SCI) and neuromyelitis optica spectrum disorders (NMOSDs). Over a period of 16 years, we retrospectively analyzed 39 patients with SCI and 21 patients with NMOSD. The demographic features and clinical presentations of both diseases were carefully documented. Etiology-specific MRI features, such as the length and distribution of the lesions, the owl's eyes sign and bright spotty lesions, were recorded and analyzed regarding their association with the clinical signs/symptoms. Patients with SCI were older than patients with NMOSD and had sudden onset of clinical symptoms with focal pain adjacent to the lesions. Concomitant spinal cord and vertebral body infarctions were frequently associated with aortic pathology (p = 0.04). In addition, artery dissection was highly associated with combined ASA and unilateral PSA infarctions and long segments of SCI (all p < 0.05). In contrast, patients with NMOSD had a relatively younger age of onset, female predominance and subacute progression of limbs weakness. As observed by MRI, the length and location of the lesions demonstrated significant differences between the two diseases (P < 0.01). The owl's eyes sign showed more frequently in patients with SCI than NMOSD (p < 0.01). The predicted prognoses in SCI and NMOSD were significantly associated with initial motor function (muscle power), after adjustments for age and gender (p < 0.01 and p = 0.02, respectively). Along with patient demographic characteristics, lesion features on MRI can help clinicians differentiate acute noncompressive myelopathy due to SCI from that due to NMOSD, which may lead to immediate initiation of adequate therapeutic measures.

Neuromyelitis optica spectrum disorder and adenocarcinoma of ovary: a novel association

Paraneoplastic neuromyelitis optica spectrum disorder (NMOSD) is a rare clinical entity with less than 40 cases described in literature until today. Paraneoplastic NMOSD in association with adenocarcinoma of ovary has not been described yet. We present a case of paraneoplastic NMOSD in association with carcinoma ovary which improved following appropriate immunomodulation with pulse intravenous methylprednisolone and azathioprine.

[Optical coherence tomography in neuromyelitis optica spectrum disorders]

Neuromyelitis optica spectrum disorders (NMOSD) are mostly relapsing inflammatory conditions of the central nervous system (CNS). In 55% of the cases of NMOSD optic neuritis (ON) is the most frequent first manifestation and can cause severe damage to the afferent visual system and the retina with resultant severe visual impairment. In recent years, investigations of the retina as part of the CNS by optical coherence tomography (OCT) has been shown to be a valid and efficient method for diagnostics and evaluation of the disease course in NMOSD. In addition, OCT not only shows severe damage of the afferent visual system due to multiple bouts of ON but also reveals NMOSD-specific intraretinal pathologies. The latter could be just as important for future differential diagnostics as for the evaluation of potential therapeutic targets. This article briefly reviews the principles of the OCT technique and describes its relevance for the diagnostics and assessment of disease course in NMOSD.

Seronegative neuromyelitis optica spectrum disorder: severe polysymptomatic presentation with successful treatment response

We report the case of a 50-year-old caucasian man presenting with lumbar pain, bilateral ataxia, central facial palsy, ophthalmoparesis and urinary retention. Cerebral MRI hinted a hyperintensity of the medulla oblongata and cervical medulla suggestive of myelitis. Cerebrospinal fluid displayed lymphocytic pleocytosis and elevated protein concentration. Without the possibility to rule out an infectious or inflammatory aetiology, antibiotics and corticosteroids were started. Nevertheless, neurological status deteriorated with loss of muscle strength and left eye amaurosis. A neuroaxis MRI exhibited encephalomyelitis with signal abnormalities involving the pons, medulla oblongata, left optic nerve and cervicodorsal medulla. Although negative for aquaporin-4-IgG antibodies, the patient fulfilled criteria for seronegative neuromyelitis optica spectrum disorder with the presence of multiple core clinical characteristics. Through early institution of corticosteroids, plasma exchange and rituximab, good functional recovery was achieved (Expanded Disability Status Scale score of 2). However, left eye amaurosis persisted despite salvage therapy with intravenous immunoglobulin.

Mechanisms for lesion localization in neuromyelitis optica spectrum disorders

Purpose of review

Neuromyelitis optica spectrum disorders (NMOSD) are severe inflammatory diseases of the central nervous system (CNS), with the presence of aquaporin 4 (AQP4)-specific serum antibodies in the vast majority of patients, and with the presence of myelin oligodendrocyte glycoprotein (MOG)-specific antibodies in approximately 40% of all AQP4-antibody negative NMOSD patients. Despite differences in antigen recognition, the preferred sites of lesions are similar in both groups of patients: They localize to the spinal cord and to the anterior visual pathway including retina, optic nerves, chiasm, and optic tracts, and – to lesser extent – also to certain predilection sites in the brain.

Recent findings

The involvement of T cells in the formation of NMOSD lesions has been challenged for quite some time. However, several recent findings demonstrate the key role of T cells for lesion formation and localization. Studies on the evolution of lesions in the spinal cord of NMOSD patients revealed a striking similarity of early NMOSD lesions with those observed in corresponding T-cell-induced animal models, both in lesion formation and in lesion localization. Studies on retinal abnormalities in NMOSD patients and corresponding animals revealed the importance of T cells for the very early stages of retinal lesions which eventually culminate in damage to Müller cells and to the retinal nerve fiber layer. Finally, a study on cerebrospinal fluid (CSF) barrier pathology demonstrated that NMOSD immunopathology extends beyond perivascular astrocytic foot processes to include the pia, the ependyma, and the choroid plexus, and that diffusion of antibodies from the CSF could further influence lesion formation in NMOSD patients.

Summary

The pathological changes observed in AQP4-antibody positive and MOG-antibody positive NMOSD patients are strikingly similar to those found in corresponding animal models, and many mechanisms which determine lesion localization in experimental animals seem to closely reflect the human situation.

Study of the cytological features of bone marrow mesenchymal stem cells from patients with neuromyelitis optica

Neuromyelitis optica (NMO) is a refractory autoimmune inflammatory disease of the central nervous system without an effective cure. Autologous bone marrow-derived mesenchymal stem cells (BM-MSCs) are considered to be promising therapeutic agents for this disease due to their potential regenerative, immune regulatory and neurotrophic effects. However, little is known about the cytological features of BM-MSCs from patients with NMO, which may influence any therapeutic effects. The present study aimed to compare the proliferation, differentiation and senescence of BM-MSCs from patients with NMO with that of age- and sex-matched healthy subjects. It was revealed that there were no significant differences in terms of cell morphology or differentiation capacities in the BM-MSCs from the patients with NMO. However, in comparison with healthy controls, BM-MSCs derived from the Patients with NMO exhibited a decreased proliferation rate, in addition to a decreased expression of several cell cycle-promoting and proliferation-associated genes. Furthermore, the cell death rate increased in BM-MSCs from patients under normal culture conditions and an assessment of the gene expression profile further confirmed that the BM-MSCs from patients with NMO were more vulnerable to senescence. Platelet-derived growth factor (PDGF), as a major mitotic stimulatory factor for MSCs and a potent therapeutic cytokine in demyelinating disease, was able to overcome the decreased proliferation rate and increased senescence defects in BM-MSCs from the patients with NMO. Taken together, the results from the present study have enabled the proposition of the possibility of combining the application of autologous BM-MSCs and PDGF for refractory and severe patients with NMO in order to elicit improved therapeutic effects, or, at the least, to include PDGF as a necessary and standard growth factor in the current in vitro formula for the culture of NMO patient-derived BM-MSCs.

Clinical course, treatment responses and outcomes in Chinese paediatric neuromyelitis optica spectrum disorder

BACKGROUND

Few data exists on paediatric neuromyelitis optica spectrum disorder (NMOSD). Here, we investigated the clinical presentation, treatment responses and long-term prognoses in a large cohort of patients with NMOSD and compared between children and adults with aquaporin-4 antibody (AQP4-IgG).

METHODS

A retrospective chart review of patients followed in multiple centres identified 127 patients with NMOSD (31 children; 96 adults). Data were collected through medical records and structured questionnaire.

RESULTS

In the paediatric cohort, median age at onset was 14 (range 7-17) years; 87% were female. AQP4 and myelin oligodendrocyte glycoprotein antibodies were detected in 82% and 16%, respectively. During a median disease duration of 48 months, 23% developed visual acuity of <6/60 Snellen, 3% were wheelchair-dependent. The frequency of brain/brainstem phenotype (18% vs 9%, p = 0.018) was more common in AQP4-IgG-positive children, while AQP4-IgG-positive adults were more likely to present transverse myelitis (TM) (44% vs 29%, p = 0.005) of all 452 episodes. Multivariable analyses showed that sustained disability was independently associated with the presence of TM (p = 0.030), brain/brainstem symptoms (p = 0.010), annualized relapse rate (p < 0.001) and possibly age of onset (p = 0.069). The reduction of ARR after azathioprine was more prominent in adults (79%) than in children (48%). Mycophenolate mofetil and rituximab decreased the relapse frequency of children, with a reduction of 94% and 100%, respectively.

CONCLUSIONS

paediatric NMOSD is a severely disabling disorder characterized by repeated brain attacks and early disability accrual. Prompt therapy including mycophenolate mofetil and rituximab should be considered to improve paediatric care.

Usefulness of MOG-antibody titres at first episode to predict the future clinical course in adults

OBJECTIVE

To analyze whether myelin oligodendrocyte glycoprotein antibody (MOG-Ab) titres at onset of the disease were different according to the clinical phenotype at presentation, and to investigate whether the titres were associated with risk of further relapses or predicted clinical outcome in adult patients. Finally, we assessed an alternative method to the classical measurement of MOG-Ab levels by serial dilutions.

METHODS

This is a retrospective study including 79 MOG-Ab-positive adult patients, whose samples were obtained at first episode. MOG-Ab were tested by cell-based assay. HEK293 cells were transfected (tHEK293) with human-MOG plasmid. Non-tHEK293 cells were used as negative controls. Assessment of antibody titres was performed by serial dilution, and delta mean fluorescence intensity ratio signal (MOG-ratio ΔMFI) by flow cytometry. MOG-ratio ΔMFI was calculated as follows: (MFI tHEK293cells- MFI non-tHEK293cells)/MFI non-tHEK293cells. MOG-ratio ΔMFI was calculated from the first serum dilution at 1:320. The association between MOG-Ab titres and risk of relapse was analyzed by Cox regression. The association between MOG-Ab titres and visual or motor disability at last follow-up was performed by binary logistic regression. Poor visual outcome was defined when patients displayed some degree of visual disability (visual acuity [VA] < 20/20) and poor motor outcome when patients displayed some degree of motor disability (Disability Status Scale [DSS] > 1). We also investigated correlations between MOG-Ab titres and MOG-ratio ΔMFI.

RESULTS

MOG-Ab titres were higher in Caucasians than in those with other ethnicities, and in patients with a more severe VA (VA ≤ 20/100) or motor disability (DSS ≥ 3.0) at onset (p = 0.006, 0.034, and 0.058, respectively). MOG-Ab titres were not associated with risk of relapses or with the final clinical outcome. MOG-ratio ΔMFI correlated with MOG-Ab titres in the whole cohort (ρ = 0.90; p < 0.001), and when stratified by initial clinical phenotype.

CONCLUSION

High MOG-Ab titres at onset are associated with a more severe presentation, but do not predict the future disease course. MOG-ratio ΔMFI is an alternative and straightforward method to determine MOG-Ab levels.

[Elderly onset case of neuromyelitis optica that developed at the age of 90]

We report a case of neuromyelitis optica (NMO) that was diagnosed at the age of 90. After initially developing visual loss in the right eye, a patient was diagnosed with optic neuritis. Although treatment with methylprednisolone therapy provided relief, 3 months later she developed optic neuritis on the other side. Visual activity recovered after further administration of methylprednisolone. At the age of 91, she presented with muscle weakness of her left extremities. A cervical MRI revealed myelitis with a longitudinally extensive spinal cord lesion from the second to fifth cervical vertebrae. Anti-AQP-4 antibody was detected in her serum. She was diagnosed with NMO and treated with methylprednisolone therapy. Subsequently, she repeatedly relapsed within a short period, developing myelitis once and optic neuritis three times within a year. However, during each hospitalization period, methylprednisolone therapy proved to be effective for relieving her symptoms. As NMO patients with onsets over 60 years of the age have been reported, medical practitioners should be aware that disease onset can occur at extremely older ages, such as 90 years old.

Neuromyelitis optica spectrum disorders: Features of aquaporin-4, myelin oligodendrocyte glycoprotein and double-seronegative-mediated subtypes

The new diagnostic classification of neuromyelitis optica spectrum disorder (NMOSD) in 2015 highlights the central role of biomarkers, such as antibodies against aquaporin-4 (AQP4-Ab), in diagnosis. Also, in approximately 20-25% of patients without AQP4-Ab (NMOSD^AQP4-) the presence of an antibody directed against myelin oligodendrocyte glycoprotein (MOG) characterizes a specific population of NMOSD patients (NMOSD^MOG+), according to their demographic and clinical data and prognoses. While double-seronegative cases (NMOSD^NEG) have not been fully described, they may correspond to the very first patients with opticospinal demyelination reported by Devic and Gault in 1894. The present report reviews the current knowledge of the pathophysiology and clinical features of NMOSD^AQP4+, NMOSD^MOG+ and NMOSD^NEG patients, and also discusses the relationship between the extended spectrum of MOG disease and NMOSD^MOG+. Finally, the current treatments for acute relapses and relapse prevention are described, with a focus on serological-based therapeutic responses and the promising new therapeutic targets.

Long-term disability in neuromyelitis optica spectrum disorder with a history of myelitis is associated with age at onset, delay in diagnosis/preventive treatment, MRI lesion length and presence of symptomatic brain lesions

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disease of the central nervous system (CNS) that preferentially targets the spinal cord and optic nerves. Increasing disability is accrued with each inflammatory attack. Disability has been shown to be an independent predictor of poor quality of life in those with NMOSD. Factors associated with increasing disability need further systematic investigation.

METHODS

We performed a multi-center retrospective chart analysis of aquaporin-4 (AQP4) seropositive NMOSD patients with a history of myelitis seen at five large referral centers for patients with NMOSD worldwide for whom thorough records including relapse history and corresponding imaging were available. Potential contributors to long-term disability were extracted including demographics, radiographic findings, and clinical characteristics. Multivariable regression modeling was conducted to determine correlates of disability in patients with NMOSD, as measured by the Expanded Disability Status Scale (EDSS).

RESULTS

One hundred eighty-two AQP4 seropositive patients (88% female) were included in this analysis. Multiple regression modeling revealed that older age at disease onset, delay in diagnosis/preventive treatment, length of longest acute myelitis lesion and presence of symptomatic brain/brainstem lesions were associated with increased disability when holding other variables constant.

CONCLUSION

While age at onset is a factor that cannot be controlled in NMOSD, we can reduce the delay in diagnosis/preventive treatment and reduce future relapses in the brain/brainstem and spinal cord. Delay in diagnosis/preventive treatment and imaging variables that contributed to increased disability support the need for improved measures for early, accurate diagnosis and management of NMOSD, and aggressive treatment of acute relapses.

Retinal nerve fibre layer thinning is associated with worse visual outcome after optic neuritis in children with a relapsing demyelinating syndrome

AIM

Optic neuritis may be monophasic or occur as part of a relapsing demyelinating syndrome (RDS), such as multiple sclerosis, aquaporin-4 antibody (AQP4-Ab) neuromyelitis optical spectrum disorder (NMOSD), or myelin oligodendrocyte glycoprotein antibody (MOG-Ab)-associated disease. The aims of this study were to test whether clinical, electrophysiological, and microstructural parameters differ in multiple-sclerosis-associated optic neuritis (MS-ON) and antibody-associated optic neuritis (Ab-ON); to identify the clinical and paraclinical characteristics of children suffering worse long-term visual outcome of RDS-optic neuritis; and to explore the relationship between RNFL thickness and clinical parameters in RDS-optic neuritis.

METHOD

Forty-two children with optic neuritis were retrospectively studied: 22 with multiple sclerosis (MS-ON) and 20 with antibody-associated demyelination (Ab-ON: MOG-Ab=16 and AQP4-Ab=4). Clinical and paraclinical features were analysed.

RESULTS

Complete recovery of visual acuity was reported in 25 out of 42 children; eight out of 38 (21%) suffered moderate or severe visual impairment (logarithm of the minimum angle of resolution [logMAR]>0.5) in their worse eye, including four out of 38 who were blind (logMAR>1.3) in their worse eye (two with multiple sclerosis, two with AQP4-Ab NMOSD). None of the children with MOG-Ab were blind. Recurrence of optic neuritis was more common in the Ab-ON group than the MS-ON group (15 out of 20 vs seven out of 22, p=0.007). Retinal nerve fibre layer (RNFL) thickness at baseline inversely correlated with visual acuity at final follow-up (r=-0.41, p=0.008). There was no significant relationship between the number of episodes of optic neuritis and mean RNFL (r=-0.08, p=0.628), nor any significant relationship between the number of episodes of optic neuritis and visual impairment (r=0.03, p=0.794).

INTERPRETATION

In children with RDS, long-term visual impairment inversely correlated with RNFL thickness, but not with the number of relapses of optic neuritis. Optical coherence tomography may have a role in assessing children with optic neuritis to monitor disease activity and inform treatment decisions.

WHAT THIS PAPER ADDS

Long-term visual impairment is reported in 40% of children with a relapsing demyelinating syndrome following optic neuritis. Relapse of optic neuritis, occurring more frequently in the non-multiple-sclerosis group. Retinal nerve fibre layer thinning is associated with worse visual outcome. Optical coherence tomography can be used alongside clinical parameters as an objective measure of neuroretinal loss.

Clinical and radiological characteristics of neuromyelitis optica spectrum disorder in the North Egyptian Nile Delta

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune demyelinating disorder of the central nervous system that was previously thought to be a subtype of multiple sclerosis (MS). Epidemiology studies of NMOSD are rare in both Middle East and North African countries. To our knowledge, there are no such studies in Egypt. Herein, we describe a case series of NMOSD patients from North Egyptian Nile Delta region and compare them to NMOSD in other parts in the Middle East and the world.

METHODS

This is a case series study of NMOSD patients who were seen at the neuroimmunology clinic, Elhadara Hospital, University of Alexandria, Egypt, from January 2017 to January 2018. We describe their clinical, serological and radiological features.

RESULTS

Our study identified twenty Egyptian patients, all of who fulfilled the 2015 international NMOSD diagnostic criteria. Ten tested positive for AQP4 antibodies in the serum while the other ten were seronegative. The mean age at onset was 27.8 years with an average disease duration of 6.8 years. There was a strong female predominance with a ratio of 5.6:1. We identified clinical features of the cohort that differ from those reported in other worldwide studies.

INTERPRETATION

This is the first NMOSD case series in Egypt. Despite some limitation in testing and access to care, there are features of our NMOSD cases that appear to be different from other worldwide cohorts reported in the literature.

Nationwide prevalence and incidence study of neuromyelitis optica spectrum disorder in Denmark

Objectives

To estimate the nationwide population-based incidence, prevalence, and geographical distribution of neuromyelitis optica (NMO) spectrum disorder (NMOSD) in Denmark based on the 2015 International Panel for NMO Diagnosis (IPND) criteria.

Methods

We conducted a multicentre, historically prospective study. Data were sourced from the Danish National Patient Registry, the Danish Multiple Sclerosis Registry, departments of neurology, and laboratories providing aquaporin-4 antibody test. Cases were selected based on the 2006 Wingerchuk and the 2015 IPND criteria and were individually validated by an expert panel.

Results

We confirmed NMO in 30 cases (2006 criteria) and NMOSD in 56 cases (2015 IPND criteria) between 2007 and 2014. Defined by the 2006 criteria, the incidence of NMO was 0.029 per 100,000 person-years (95% confidence interval [CI] 0.014–0.051), and the prevalence (aged 16 years and older) was 0.566 per 100,000 (95% CI 0.370–0.830). Based on the 2015 IPND criteria, the incidence of NMOSD was 0.070 per 100,000 person-years (95% CI 0.046–0.102), and the prevalence (aged 16 years and older) was 1.09 per 100,000 (95% CI 0.808–1.440), without regional differences.

Conclusions

Our estimates of incidence and prevalence are similar to other Caucasian population–based studies using the 2015 IPND criteria. We found no geographical clustering in Denmark.

Racial differences in neuromyelitis optica spectrum disorder

OBJECTIVE

We aimed to evaluate racial differences in the clinical features of neuromyelitis optica spectrum disorder.

METHODS

This retrospective review included 603 patients (304 Asian, 207 Caucasian, and 92 Afro-American/Afro-European), who were seropositive for anti-aquaporin-4 antibody, from 6 centers in Denmark, Germany, South Korea, United Kingdom, United States, and Thailand.

RESULTS

Median disease duration at last follow-up was 8 years (range 0.3-38.4 years). Asian and Afro-American/Afro-European patients had a younger onset age than Caucasian patients (mean 36, 33, and 44 years, respectively; p < 0.001). During the disease course, Caucasian patients (23%) had a lower incidence of brain/brainstem involvement than Asian (42%) and Afro-American/Afro-European patients (38%) (p < 0.001). Severe attacks (visual acuity ≤0.1 in at least one eye or Expanded Disability Status Scale score ≥6.0 at nadir) at onset occurred more frequently in Afro-American/Afro-European (58%) than in Asian (46%) and Caucasian (38%) patients (p = 0.005). In the multivariable analysis, older age at onset, higher number of attacks before and after immunosuppressive treatment, but not race, were independent predictors of severe motor disabilities at last follow-up.

CONCLUSION

A review of a large international cohort revealed that race affected the clinical phenotype, age at onset, and severity of attacks, but the overall outcome was most dependent on early and effective immunosuppressive treatment.

Sex differences in autoimmune disorders of the central nervous system

Stronger adaptive immune responses in females can be observed in different mammals, resulting in better control of infections compared to males. However, this presumably evolutionary difference likely also drives higher incidence of autoimmune diseases observed in humans. Here, we summarize sex differences in the most common autoimmune diseases of the central nervous system (CNS) and discuss recent advances in the understanding of possible underlying immunological and CNS intrinsic mechanisms. In multiple sclerosis (MS), the most common inflammatory disease of the CNS, but also in rarer conditions, such as neuromyelitis optica spectrum disorders (NMOSD) or neuronal autoantibody-mediated autoimmune encephalitis (AE), sex is one of the top risk factors, with women being more often affected than men. Immunological mechanisms driving the sex bias in autoimmune CNS diseases are complex and include hormonal as well as genetic and epigenetic effects, which could also be exerted indirectly via modulation of the microbiome. Furthermore, CNS intrinsic differences could underlie the sex bias in autoimmunity by differential responses to injury. The strong effects of sex on incidence and possibly also activity and progression of autoimmune CNS disorders suggest that treatments need to be tailored to each sex to optimize efficacy. To date, however, due to a lack of systematic studies on treatment responses in males versus females, evidence in this area is still sparse. We argue that studies taking sex differences into account could pave the way for sex-specific and therefore personalized treatment.

Clinical Characteristics of Anti-aquaporin 4 Antibody Positive Optic Neuritis in Japan

To investigate the clinical characteristics and the effectiveness of maintenance therapy of anti-AQP4 antibody positive optic neuritis in Japanese patients, medical records from 69 patients (103 eyes) were retrospective reviewed. The status of relapse in patients who received maintenance therapy following acute therapy was compared with that before maintenance therapy in patients who started maintenance therapy ≥6 months after acute therapy. In Japan, anti-AQP4 antibody positive optic neuritis was characterized by older onset age and poor visual outcome. The yearly rate and total number of relapses were lower when maintenance therapy was followed immediately after acute therapy.

A prospective case-control study comparing optical coherence tomography characteristics in neuromyelitis optica spectrum disorder- optic neuritis and idiopathic optic neuritis

Background

Neuromyelitis optica spectrum disorder-optic neuritis (NMOSD-ON) can now be distinguished from other types of ON as a specific disease by the Aquaporin-4 antibody (AQP4-Ab) test. NMOSD-ON can cause severe retinal nerve fiber layer (RNFL) damage. The optical coherence tomography (OCT) characteristics between NMOSD- ON and idiopathic optic neuritis (IDON) were seldom studied in Asians.

Methods

This prospective case-control study involved 152 eyes from 143 optic neuritis (ON) patients. All the patients were divided into either the NMOSD-ON group or the IDON group based on the AQP4-Ab test. The retinal nerve fiber layer thickness (RNFLT), retinal thickness (RT), and choroidal thickness (CT) were measured by spectral-domain OCT and compared to the 60 age- and gender-matched healthy controls. The association between RNFLT and best corrected visual acuity (BCVA) was examined.

Results

The RNFLT was significantly thinner in all ON patients than in healthy controls, while NMOSD-ON eyes were significantly more affected than IDON eyes in all quadrants (p < 0.01). NMOSD-ON patients had stronger visual function impairment than IDON patients (p < 0.01). RNFLT was related to BCVA in both the NMOSD-ON and IDON groups. Microcystic macular edema (MME) was identified in 28 patients (19.58%) and in 29 of 152 eyes (19.08%), including 20 of 40 eyes (50%) previously affected by ON. MME was more common in patients with NMOSD-ON (32.2%) than in those with IDON (10.75%) (p = 0.001).

Conclusions

The NMOSD-ON group had more pronounced RNFLT thinning and visual function impairment than the IDON group. MME prevalence was higher in NMOSD-ON and was associated with higher frequency of clinical relapses.

Neuromyelitis optica spectrum disorder presenting in an octogenarian

This case describes an 81-year-old woman with a history of Sjögren's syndrome presenting with recurrent falls and poor balance. She subsequently developed new and rapidly evolving neurology including hyperaesthesia, spastic paraplegia and sphincteric dysfunction. Following serial clinical reviews and detailed investigations, MRI (brainstem and cervicothoracic spine) and a seropositive result for aquaporin 4 IgG, a diagnosis of neuromyelitis optica spectrum disorder (NMOSD) was made. This case describes the clinical course of this index patient with an unusual late age of onset. The report also includes a discussion on NMOSD. We review aspects of terminology, brief epidemiology, pathogenesis, notable autoimmune associations, variance in clinical presentation and current diagnostic criteria. We also review the importance of distinguishing NMOSD from multiple sclerosis in view of the significant implications for treatment and prognosis.

Clinical Characteristics, Treatment Outcomes and Predictive Factors in Optic Neuritis

Background:

The causes, clinical presentations and treatment outcomes of optic neuritis are distinct among different populations. Early diagnosis based on clinical presentations plays an important role in treating optic neuritis patients.

Objective:

The study aimed to determine clinical characteristics, treatment outcomes and predictive factors of treatment outcomes in optic neuritis patients with and without demyelinating disease.

Methods:

A retrospective descriptive study of optic neuritis patients carried out between January 2009 and December 2016 was done. Univariate analysis and multivariate logistic regression analysis were used to evaluate the predictive factors of treatment outcomes.

Results:

Among 150 patients with optic neuritis, 58 patients were diagnosed with Neuromyelitis Optica Spectrum Disease (NMOSD), 23 patients were diagnosed with Multiple Sclerosis (MS) and 69 patients were idiopathic. The age at presentation in the NMOSD group was significantly younger than the MS group and the idiopathic group. The female:male ratio was significantly lower in the idiopathic group than in the NMOSD group. The initial Best Corrected Visual Activity (BCVA) of 20/20-20/60 (p = 0.001) and the idiopathic group (p =0.030) was associated with good visual outcomes. Initial BCVA of < 20/200 (p = 0.009) and the NMOSD group (p < 0.001) was associated with poor visual outcomes.

Conclusion:

NMOSD is a more common cause of optic neuritis than MS in Thai population. Female patients with poor initial VA, poor response to steroids treatment, and presenting recurrent attacks are highly suspicious for NMOSD. Optic neuritis without associated demyelinating disease has a better visual outcome and lower recurrence rate.

Blood Brain Barrier Permeability Could Be a Biomarker to Predict Severity of Neuromyelitis Optica Spectrum Disorders: A Retrospective Analysis

Background: Blood-brain barrier (BBB) pathology exists in neuromyelitis optica spectrum disorders (NMOSD). However, the clinical use of BBB permeability, such as predicting disease severity of NMOSD, has rarely been studied in a large cohort of patients.

Objectives: The current study explored the association between BBB permeability and clinical parameters in order to assess if BBB permeability could be a biomarker to predict disease severity and clinical characteristics of NMOSD.

Methods: Among 69 enrolled NMOSD patients, 47 with albumin index over 5 × 10⁻³ were assigned to the increased BBB permeability group, and the remaining 22 were to the normal BBB permeability group. Disease severity was assessed using the Expanded Disability Status Scale (EDSS).

Results: Patients in the increased BBB permeability group had significantly higher EDSS scores, anti-aquporin-4 immunoglobulin G titers, more dense cerebrospinal fluid protein concentrations, white blood cell counts, myelin basic protein levels and more dense complement 3 concentrations than found in the comparative normal BBB permeability group. The albumin index was positively correlated to the length of lesions in spinal cord.

Conclusions: BBB permeability was associated with clinical features, laboratory results and radiological data of NMOSD patients, and may be a potential biomarker to predict disease severity and clinical characteristics of NMOSD.

Multiple sclerosis and neuromyelitis optica spectrum disorders in Malaysia: A comparison in different ethnic groups

We performed a retrospective observational analytical study looking at the frequencies and characteristics of multiple sclerosis(MS) and neuromyelitis optica spectrum disorders(NMOSD) in consecutive patients with idiopathic inflammatory demyelinating disease (IIDDs) attending three centers (2009-2017). Of 523 patients with IIDDs, there were 173 patients with NMOSD and 230 patients with MS. The percentage of NMOSD: IIDDs was 33%. The percentage of NMOSD:Total MS and NMOSD cohort was 43%. Of 141 seropositive NMOSD patients, 134(95%) were from the three main ethnic groups. The percentage of seropositive NMOSD to IIDDs and to combined MS and NMOSD was 26.9% and 35% respectively. Ratios of MS to NMOSD were nearly equal at 1.3 to 1.0, reinforcing the high ratio of NMOSD to MS in Asia. Nearly half of the Chinese cohort were seropositive ie; 71/141 (50%) with the remainder being Malays; 56/141 (39.7%) and Indians; 7/141 (5%). Amongst the other indigenous groups seropositivity was seen in 2 each of Iban, Bajau, Kadazan descent as well as one of Bidayuh origin. Comparatively, seropositivity in NMOSD is commoner amongst the Chinese compared to the Malays (p ≤ 0.005) and Indians, p ≤ 0.05 with ratios as high as 10:1. In the MS group of 230 subjects, 123(53.5%) were Malays (ratio of MS:NMOSD of 2:1), 41(17.8%) were Chinese, (ratio of MS:NMOSD of 0.5:1.0) and 54 (23.5%)were Indians (ratios of MS:NMOSD of 5:1 amongst the Indians). The remainder from East Malaysia were made up of 2 each of Kadazans, Ibans and Bajaus including 3 each of Bidayuh and Eurasian descent. Comparatively, in the NMOSD and MS cohorts a female preponderance was noted more so amongst Chinese NMOSD patients, with rare familial occurrence in both but more in Malay MS/NMOSD patients. This study also highlighted some of the inter-ethnic differences in presentation of MS and NMOSD amongst the 3 main ethnic races in Malaysia and confirms indigenous races having MS/NMOSD which needs further research. It also reviewed current literature on similar inter-ethnic differences world wide. To conclude, MS and NMOSD are the commonest demyelinating diseases seen in Malaysia with interesting inter-ethnic differences and similarities.

Acute intractable vomiting: Do I belong somewhere else?

Patients suffering from acute intractable vomiting are usually treated in the Gastroenterology department. The causes of acute intractable vomiting range from acute pancreatitis and acute intestinal obstruction to cardiac causes like acute myocardial infarction and neurological causes like posterior circulation stroke. However, most of the underlying causes of acute intractable vomiting also produce other telltale signs/symptoms. Rarely, isolated acute intractable vomiting may be the initial symptom of a recurrent neurological syndrome of neuromyelitis optica spectrum disorder (NMOSD). Not only can it be promptly treated if diagnosed correctly, but also a timely diagnosis may help in prevention of recurrent neurological deficits, which can sometimes be life threatening. We present three cases of NMOSD that presented with intractable vomiting and were treated in a Gastroenterology facility prior to their diagnosis.