Neuromyelitis optica: Concepts in evolution

Low carbohydrate diet score and odds of neuromyelitis optica spectrum disorder: A case-control study

Introduction: Neuromyelitis optica spectrum disorder (NMOSD) is a demyelinating inflammatory disease of The Central nervous system. We aimed to investigate the association between low carbohydrate diet (LCD) and NMOSD odds. Method: Seventy NMOSD patients with definite diagnosis and 164 hospital-based controls were enrolled in this case-control study. Dietary data was obtained using a validated 168-item food frequency questionnaire. To determine the LCD score, participants were stratified into 11 groups according to carbohydrate, protein, fat, animal fat, animal protein, vegetable fat and vegetable protein intakes. Higher intake of protein and fat, and lower intake of carbohydrate received a higher score between 0-10. Macronutrients scores were summed together and LCD scores calculated. The association between LCD scores and likelihood of being assigned to NMOSD group was investigated using multiple regression models. Results: Total LCD scores increased from the median of 21.00 in the first decile to 53.00 in the tenth decile of LCD score. After adjustment for confounding factors including age, gender, BMI, energy intake, cigarette smoking and alcohol consumption, an inverse association was detected between LCD scores and odds of NMOSD. The odds of suffering from NMOSD declined significantly about 78% (OR: 0.22; 95% CI: 0.05-0.87) and 76% (OR: 0.24; 95% CI: 0.06-0.93) in the fifth and sixth deciles of LCD score compared to the first decile. Conclusion: From the obtained results it can be speculated that higher carbohydrate and lower protein and fat intakes may be associate with the increased odds of NMOSD. However, further studies are needed to confirm these results.

[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.

A new M23-based ELISA assay for anti-aquaporin 4 autoantibodies: diagnostic accuracy and clinical correlation

Purpose

Although many assays have been developed to detect anti-aquaporin-4 (AQP4) antibodies, most of these assays require sophisticated techniques and are thus only available at specialized laboratories. The aim of this study was to evaluate the analytical and clinical performance of a new commercial enzyme-linked immunosorbent assay (ELISA RSR, AQP4 Ab Version 2) to detect anti-AQP4 antibodies performed on a fully automated system (SkyLAB 752).

Methods

Serum samples from 64 patients with neuromyelitis optica spectrum disorders (NMOSD) (including NMO, longitudinally extensive myelitis-LETM, optical neuritis and myelitis) and 27 controls were tested for anti-AQP4 antibodies. All sera were previously tested using an indirect immunofluorescence (IIF) method on primate tissue, as the reference method. Commercial control sera were used to determine within-run, between-day and within-laboratory precision (CLSI guidelines).

Results

At a cut-off value of 2.1 U/mL as determined by ROC curves, sensitivity and specificity for NMO were 83.3% and 100%, respectively. The ELISA assay provided 100% concordant results with the reference IIF method. The median concentration of anti-AQP4 antibodies was statistically higher in patients with NMO than in patients with LETM (p = 0.0006) or with other NMOSD and in controls (p < 0.0001). At the concentration of 12.4 and 28.1 U/mL, the within-run, between-day and within-laboratory coefficients of variation (CV) were 3.2% and 3%, 7.6% and 7.4%, and 8.2% and 8.0%, respectively.

Conclusions

This new ELISA method performed on a fully automated system, showed high sensitivity and absolute specificity, good CV in precision tests, and provided observer-independent quantitative results.

Neuromyelitis optica spectrum disorders: long-term safety and efficacy of rituximab in Caucasian patients

Objective:

To assess the long-term benefit-risk profile of repeated courses of rituximab in Caucasian patients affected by neuromyelitis optica (NMO) and related disorders, in everyday clinical practice.

Methods:

This is a prospective observational study performed at San Raffaele Hospital, Milan, Italy. From February 2006, we recruited 21 patients affected by NMO and NMO spectrum of disorders (NMOSD) whom underwent at least one cycle of intravenous (i.v.) rituximab and then were followed for at least 2 years.

Results:

At a mean follow-up time of 48 months, we observed a significant reduction of the annualized relapse rate (ARR), from 2.0 to 0.16 ( p < 0.01); and of the median Expanded Disability Status Scale (EDSS), from 5.5 to 4.0 ( p < 0.013). There were 12 patients (57%) who remained disease free during the follow-up period. Five patients (24%) reported mild hematological adverse events. Serious infectious adverse events were reported by another four patients: These were all wheelchair bound at the beginning of their rituximab treatment.

Conclusions:

A fixed treatment scheme of rituximab, with re-treatment every 6 months, was efficacious for NMO and NMOSD, with a good safety profile; however, to obtain an even better benefit-risk ratio, close monitoring of CD19+ B cells should be performed before the re-treatment of patients with high-level disability, concomitant leukopenia and hypogammaglobulinemia.

Epidemiology of neuromyelitis optica in the world: a systematic review and meta-analysis

Background. Neuromyelitis optica (Devic's disease) is a severe autoimmune inflammatory disorder of the central nervous system. Epidemiological aspects of NMO have not been systemically reviewed. In this study we systematically reviewed and assessed the quality of studies reporting the incidence and/or prevalence of NMO across the world. Methods. A comprehensive literature search using MEDLINE, EMBASE, and Web of Science for the terms “Neuromyelitis optica,” “devic disease,” “incidence,” “prevalence,” and “epidemiology” was conducted on January 31, 2015. Study quality was assessed using an assessment tool based on recognized guidelines and designed specifically for this study. Results. A total of 216 studies were initially identified, with only 9 meeting the inclusion criteria. High level of heterogeneity amongst studies precluded a firm conclusion. Incidence data were found in four studies and ranged from 0.053 per 100,000 per year in Cuba to 0.4 in Southern Denmark. Prevalence was reported in all studies and ranged from 0.51 per 100,000 in Cuba to 4.4 in Southern Denmark. Conclusion. This review reveals the gaps that still exist in the epidemiological knowledge of NMO in the world. Published studies have different qualities and methodology precluding a robust conclusion. Future researches focusing on epidemiological features of NMO in different nations and different ethnic groups are needed.

Allogeneic hematopoietic stem cell transplantation for neuromyelitis optica

Neuromyelitis optica is a rare neurological autoimmune disorder characterized by a poor prognosis. Immunosuppression can halt disease progression, but some patients are refractory to multiple treatments, experiencing frequent relapses with accumulating disability. Here we report on durable clinical remissions after allogeneic hematopoietic stem cell transplantation in 2 patients suffering from severe forms of the disease. Immunological data evidenced disappearance of the pathogenic antibodies and regeneration of a naive immune system of donor origin. These findings correlated with evident clinical and radiological improvement in both patients, warranting extended clinical trials to investigate this promising therapeutic option.

Nervous System Complications of Systemic Viral Infections

Invasion of the central nervous system (CNS) by viral agents typically produces a meningoencephalitis in which either meningitis or encephalitis may predominate. Viruses may also infect cranial or spinal blood vessels to produce ischemic injury. Viral and other infections may also elicit a host immune response which is cross-reactive with components of the neural tissue, resulting in encephalomyelitis, transverse myelitis, injury to peripheral nerves, or optic neuritis. This chapter discusses the pathogenesis of CNS viral infections and reviews clinical features of these disorders, major agents responsible in immunocompromised and immunocompetent individuals, and treatment. Prion diseases and postinfectious viral CNS syndromes including postinfectious encephalomyelitis, acute hemorrhagic leukoencephalitis, cerebellar ataxia, and transverse myelitis are also discussed.

A case of neuromyelitis optica misdiagnosed as cervicogenic headache

Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the central nervous system associated with longitudinally extensive myelitis and optic neuritis. It is characterized by relapses that lead to blindness and paralysis sequelaes. But, this is rare disease; therefore high clinical suspicion for a correct diagnosis and proper examinations are not easy. However, early diagnosis is essential to prevent sequelae. We report the case of NMO with headache. A 30-year male patient who suffered headache visited our pain clinic because of aggravated pain despite treatment. The cause of the pain was revealed as NMO by more detailed previous history and examination.

IL-22 secreting CD4+ T cells in the patients with neuromyelitis optica and multiple sclerosis

Interleukin (IL)-22 secreting CD4(+) T (Th22) cells and IL-22 are involved in the pathogenesis of autoimmune disease, but their role in neuromyelitis optica (NMO) and multiple sclerosis (MS) is unclear. We measured the proportion of Th22, Th17, CD4(+)IL-22(+)IL-17A(+) T cells and serum IL-22 in NMO and MS patients. The proportion of Th22 cells, Th17 cells and serum IL-22 were increased in patients with NMO and MS. Our findings suggest that increased Th22 cells may play an important role in the pathogenesis of NMO and MS.

Visual evoked potentials in early diagnosis of demyelinating diseases--a case report of Devic's disease

BACKGROUND

Devic's disease, also known as neuromyelinitis optica (NMO), is a severe, rare demyelinating disorder, previously considered to be a form of multiple sclerosis (MS). The aim of this study was to present the case report of 21-year-old woman with a very early diagnosis of Devic's disease, established following electrophysiological testing.

CASE REPORT

A 21-year-old woman was referred to Warsaw Medical University, Department of Ophthalmology, with subjective visual impairment. The patient underwent a full clinical examination, colour vision and Goldmann visual field testing, fluorescein angiography, OCT, multifocal ERG, and visual evoked potentials (VEPs).

CONCLUSIONS

Visual evoked potentials are a very useful diagnostic tool in optic nerve neuropathies. In our patient, the electrophysiological testing allowed us to establish a proper diagnosis very early, before typical clinical signs of Devic's disease.

Detection of anti-aquaporin-4 antibodies in neuromyelitis optica: comparison of tissue-based and cell-based indirect immunofluorescence assays and ELISA

NMO-IgG against aquaporin-4 (AQP4) is a specific marker for neuromyelitis optica (NMO). We evaluated the performance of different NMO-IgG detecting methods. In 124 sera (from 54 with NMO spectrum disorders including nine with NMO, ten with multiple sclerosis including two with OSMS, and 60 with other neurological diseases), NMO-IgG was measured with tissue-based indirect immunofluorescence (IIF-tissue) using mouse cerebellum, cell-based IIF (IIF-AQP4) using transfected HEK293 cells which express human AQP4, and AQP4 autoantibody detecting enzyme linked immunosorbent assay (ELISA-AQP4). The sensitivities and specificities of three assays were 44.4-55.6% and 87.0-92.2% for detecting NMO, and 11.1-20.4% and 95.7-97.1% for detecting NMO spectrum disorders. Although there was no significant difference, the patients with NMO or NMO spectrum disorders showed higher rates of seropositivity in the ELISA-AQP4 vs. IIF assays. Out of the 19 sera with NMO-IgG, in at least one test, only six (31.6%) were found to be positive by all three assays. Among the three methods, the ranges of co-negativities, co-positivities, and agreement were 77.4-97.4%, 42.9-75.0%, and 91.1-95.2% (kappa 0.475-0.641), respectively. In patients who had positive ELISA-AQP4 results, IIF-AQP4 positivity was associated with NMO (P = 0.01). In summary, we observed an increased prevalence of NMO-IgG in patients with NMO and NMO spectrum disorders. ELISA-AQP4 may be more sensitive and specific when confirmed by IIF-AQP4.

Neuromyelitis optica: aquaporin-4 based pathogenesis mechanisms and new therapies

Neuromyelitis optica (NMO) is an autoimmune 'aquaporinopathy' of the central nervous system that causes inflammatory demyelinating lesions primarily in spinal cord and optic nerve, leading to paralysis and blindness. NMO lesions show loss of aquaporin-4 (AQP4), GFAP and myelin, infiltration of granulocytes and macrophages, and perivascular deposition of activated complement. Most patients with NMO are seropositive for immunoglobulin autoantibodies (AQP4-IgG) against AQP4, the principal water channel of astrocytes. There is strong evidence that AQP4-IgG is pathogenic in NMO, probably by a mechanism involving complement-dependent astrocyte cytotoxicity, causing leukocyte infiltration, cytokine release and blood-brain barrier disruption, which leads to oligodendrocyte death, myelin loss and neuron death. Here, we review the evidence for this and alternative proposed NMO pathogenesis mechanisms, such as AQP4-IgG-induced internalization of AQP4 and glutamate transporters, complement-independent cell-mediated cytotoxicity, and AQP4-IgG inhibition of AQP4 water transport function. Based on the initiating pathogenic role of AQP4-IgG binding to astrocyte AQP4 in NMO, selective blocker therapies are under development in which AQP4-targeted monoclonal antibodies or small molecules block binding of AQP4-IgG to astrocytes and consequent downstream pathology.

Evaluation of a multiparametric immunofluorescence assay for standardization of neuromyelitis optica serology

BACKGROUND

Neuromyelitis optica (NMO) is a severely disabling autoimmune disorder of the central nervous system, which predominantly affects the optic nerves and spinal cord. In a majority of cases, NMO is associated with antibodies to aquaporin-4 (AQP4) (termed NMO-IgG).

AIMS

In this study, we evaluated a new multiparametric indirect immunofluorescence (IIF) assay for NMO serology.

METHODS

Sera from 20 patients with NMO, 41 patients with multiple sclerosis (MS), 30 healthy subjects, and a commercial anti-AQP4 IgG antibody were tested in a commercial composite immunofluorescence assay ("Neurology Mosaic 17"; Euroimmun, Germany), consisting of five different diagnostic substrates (HEK cells transfected with AQP4, non-transfected HEK cells, primate cerebellum, cerebrum, and optic nerve tissue sections).

RESULTS

We identified AQP4 specific and non-specific fluorescence staining patterns and established positivity criteria. Based on these criteria, this kit yielded a high sensitivity (95%) and specificity (100%) for NMO and had a significant positive and negative likelihood ratio (LR+ = ∞, LR- = 0.05). Moreover, a 100% inter- and intra-laboratory reproducibility was found.

CONCLUSIONS

The biochip mosaic assay tested in this study is a powerful tool for NMO serology, fast to perform, highly sensitive and specific for NMO, reproducible, and suitable for inter-laboratory standardization as required for multi-centre clinical trials.

Integrative continuum: accelerating therapeutic advances in rare autoimmune diseases

Autoimmune diseases are chronic, life threatening, and of burgeoning public health concern. They rank among the 10 most common causes of death in women, and some have incidence rates surpassing those of heart disease and cancer. Emerging information regarding molecular and cellular mechanisms affords opportunities for the discovery of novel therapeutic strategies or the repurposing of FDA-approved pharmacologic agents. Yet, obstacles to drug development amplify as an inverse function of the incidence of rare autoimmune disease; challenges include heterogeneous clinical presentation, paucity of definitive biomarkers, and poorly validated measures of therapeutic response. An integrative continuum model to address these challenges is being applied to neuromyelitis optica (NMO)-a potentially devastating neurodegenerative process that has had limited therapeutic options. This model links target discovery with pharmacologic application to accelerate improved clinical efficacy. The application of such innovative strategies may help researchers overcome barriers to therapeutic advances in NMO and other rare autoimmune diseases.

Plasma sCD28, sCTLA-4 levels in neuromyelitis optica and multiple sclerosis during relapse

BACKGROUND

Soluble forms of CD28 (sCD28) and CTLA-4 (sCTLA-4) were associated with many autoimmune diseases like Sjögren's syndrome, systemic lupus erythematosus, asthma, and autoimmune myasthenia gravis. However, sCD28 and sCTLA-4 in neuromyelitis optica (NMO) and multiple sclerosis (MS) patients were less studied.

OBJECTIVE

To measure the plasma sCD28, sCTLA-4 in NMO and MS patients, and investigate whether sCD28 and sCTLA-4 possible use as sensitive biomarkers for diseases activity.

METHODS

Plasma concentrations of sCD28, sCTLA-4 were measured by an enzyme-linked immunosorbent assay (ELISA) in NMO (n=22), MS (n=21) patients and controls (n=18).

RESULTS

The concentration of sCD28 levels were higher in the inflammatory demyelinating diseases cohort compared with the controls (NMO, p=0.034; MS, p=0.026) and the levels of sCD28 were slightly higher in NMO compared with MS. The sCTLA-4 levels were lower in the MS subgroup compared with the controls (p=0.032). Both sCD28 and sCTLA-4 did not show any correlation with EDSS score in NMO and MS patients.

CONCLUSIONS

Our study revealed for the first time that the levels of increased plasma sCD28 and decreased plasma sCTLA-4 in NMO and MS patients, but had little correlation with clinical presentations.