Is Devic's neuromyelitis optica a separate disease? A comparative study with multiple sclerosis

Inflammatory lesions of the brainstem: Keys for the diagnosis by MRI

OBJECTIVE

To describe the magnetic resonance imaging (MRI) findings for the most common inflammatory and immune-mediated diseases that involve the brainstem.

CONCLUSION

Inflammatory lesions involving the brainstem are associated with a wide range of autoimmune, infectious, and paraneoplastic syndromes, making the differential diagnosis complex. Being familiar with these entities, their clinical characteristics, and their manifestations on MRI, especially the number of lesions, their shape and extension, and their appearance in different sequences, is useful for orienting the radiological diagnosis.

Neuromyelitis optica spectrum disorder: pathophysiological approach

Aim: To review the main pathological findings of Neuromyelitis Optica Spectrum Disorder (NMOSD) associated with the presence of autoantibodies to aquaporin-4 (AQP4) as well as the mechanisms of astrocyte dysfunction and demyelination. Methods: An comprehensive search of the literature in the field was carried out using the database of The National Center for Biotechnology Information from . Systematic searches were performed until July 2022. Results: NMOSD is an inflammatory and demyelinating disease of the central nervous system mainly in the areas of the optic nerves and spinal cord, thus explaining mostly the clinical findings. Other areas affected in NMOSD are the brainstem, hypothalamus, and periventricular regions. Relapses in NMOSD are generally severe and patients only partially recover. NMOSD includes clinical conditions where autoantibodies to aquaporin-4 (AQP4-IgG) of astrocytes are detected as well as similar clinical conditions where such antibodies are not detected. AQP4 are channel-forming integral membrane proteins of which AQ4 isoforms are able to aggregate in supramolecular assemblies termed orthogonal arrays of particles (OAP) and are essential in the regulation of water homeostasis and the adequate modulation of neuronal activity and circuitry. AQP4 assembly in orthogonal arrays of particles is essential for AQP4-IgG pathogenicity since AQP4 autoantibodies bind to OAPs with higher affinity than for AQP4 tetramers. NMOSD has a complex background with prominent roles for genes encoding cytokines and cytokine receptors. AQP4 autoantibodies activate the complement-mediated inflammatory demyelination and the ensuing damage to AQP4 water channels, leading to water influx, necrosis and axonal loss. Conclusions: NMOSD as an astrocytopathy is a nosological entity different from multiple sclerosis with its own serological marker: immunoglobulin G-type autoantibodies against the AQP4 protein which elicits a complement-dependent cytotoxicity and neuroinflammation. Some patients with typical manifestations of NMSOD are AQP4 seronegative and myelin oligodendrocyte glycoprotein positive. Thus, the detection of autoantibodies against AQP4 or other autoantibodies is crucial for the correct treatment of the disease and immunosuppressant therapy is the first choice.

Neuromyelitis Optica Spectrum Disorder and Autoimmune Rheumatological Diseases: A Report of Two Cases and Literature Review

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune disorder, and its association with other autoinflammatory diseases has been reported in this study. In this article, we are discussing two patients with neuromyelitis optica who show evidence of autoimmune rheumatic diseases. The first case presented with acute myelitis and was diagnosed with NMOSD; she developed clinical features of Behçet’s disease during follow-up, making it the second reported case worldwide. The second case presented with neuromyelitis optica and was found to have strongly positive Sjogren’s serology.

[Clinical and epidemiological aspects of neuromyelitis optic spectrum diseases in the russian population]

OBJECTIVE

To present clinical and epidemiological aspects of neuromyelitis optica spectrum disorders (NMOSD) in the Russian Federation.

MATERIAL AND METHODS

We studied 142 patients who met diagnostic criteria of 2015 for NMOSD. Sex, age at disease onset, presence or absence of aquaporin-4 immunoglobulin G antibodies (AQP4-IgG), mail clinical symptoms, oligoclonal IgG, therapy for the treatment of exacerbations and prevention of exacerbations, compliance with 2006 diagnostic criteria were assessed.

RESULTS

The prevalence of women is 4.26:1, the most frequent age at disease onset is 18-29 years (36% of cases). The laboratory aspects of the disease are characterized and approaches to the treatment and prevention of exacerbations of NMOSD in patients of the Russian population are evaluated. Approaches to diagnostics are compared depending on the applied diagnostic criteria (34% of patients do not meet neuromyelitis optica 2006 diagnostic criteria). A prognosis for the prevalence of NMOSD in the Russian population has been proposed: 0.45-4.21/100000.

CONCLUSION

This is the first published data on clinical and epidemiological characteristics of NMOSD in the Russian Federation.

Application of the 2015 neuromyelitis optica spectrum disorders diagnostic criteria in a cohort of Chinese patients

BACKGROUND

There is no validation study evaluating 2015 International Panel for neuromyelitis optica (NMO) spectrum disorders (NMOSD) diagnosis (IPND) criteria in Chinese population. The association of myelin oligodendrocyte glycoprotein-immunoglobulin-G (MOG-IgG) with NMOSD was also not investigated in previous validation studies. Hence, we aimed to validate the 2015 NMOSD criteria in a cohort of Chinese patients, and to assess the association between MOG-IgG and NMOSD.

METHODS

We applied both the 2006 NMO and the 2015 NMOSD diagnostic criteria to all suspected NMOSD inpatients at the Department of Neurology of Chinese PLA general hospital diagnosed between 2016 and 2019. Demographics, core clinical features, AQP4-IgG and MOG-IgG status were retrieved and analyzed.

RESULTS

A total of 185 patients fulfilling the 2015 NMOSD criteria (154 AQP4-IgG positive, 23 AQP4-IgG negative, 8 AQP4-IgG status unknown) were included, whereas only 43.2% (80/185) fulfilled the 2006 NMO criteria. After assuming all the NMOSD patients with unknown AQP4-IgG status, 69.7% (129/185) still fulfilled the 2015 NMOSD criteria, whereas only 39.5% (73/185) met the 2006 NMO diagnostic criteria (p < 0.001). Most NMOSD patients (n = 55, 29.7%) disqualified because of not meeting the criterion of dissemination in space. The median time to diagnosis was 3 months (129 patients, range: 1-145 months) by the 2015 NMOSD criteria and 10 months (73 patients, range: 1-185 months) by the 2006 NMO criteria (log rank test: p = 0.002). Positive MOG-IgG was found in 28.6% (4/14) of the AQP4-IgG negative and 2.8% (1/36) of the AQP4-IgG positive NMOSD patients (p = 0.006). NMOSD with MOG-IgG was more frequently in male (3/1 vs. 2/33, p = 0.004) and with younger onset age (24.8 vs. 41.4, p = 0.045), in comparison with NMOSD with AQP4-IgG.

CONCLUSION

The 2015 NMOSD criteria markedly improved the diagnostic rate and reduced the time taken to diagnosis in a cohort of Chinese patients, even with unknown AQP4-IgG status, in comparison with the 2006 NMO criteria. Not meeting the criterion of dissemination in space, that is, having isolated core clinical feature, was the main factor precluding NMOSD diagnosis under assumption of unknown AQP4-IgG status. NMOSD with MOG-IgG was not uncommon in NMOSD without AQP4-IgG and had unique features regarding gender predominance and onset age.

Identification of geraldol as an inhibitor of aquaporin‑4 binding by NMO‑IgG

Neuromyelitis optica (NMO) is a severe neurological demyelinating autoimmune disease that affects the optic nerves and spinal cord. There is currently no effective cure or therapy. Aquaporin-4 (AQP4) is a known target of the autoimmune antibody NMO-IgG. Therefore, binding of NMO-IgG to AQP4, and subsequent activation of antibody-mediated and complement-dependent cytotoxicity (CDC), are thought to underlie the pathogenesis of NMO. In the present study, a cell-based high-throughput screening approach was developed to identify molecular inhibitors of NMO-IgG binding to AQP4. Using this approach, extracts from the herb Petroselinum crispum were shown to have inhibitory effects on NMO-IgG binding to AQP4, and the natural compound geraldol was purified from the herb extracts. Analytical high performance liquid chromatography, electrospray ionization-mass spectrometry and nuclear magnetic resonance analyses confirmed the identity of the isolated compound as geraldol, a flavonoid. Geraldol effectively blocked binding of NMO-IgG to AQP4 in immunofluorescence assays and decreased CDC in NMO-IgG/complement-treated FRTL-AQP4 cells and primary astrocytes. Geraldol exhibited low cytotoxicity, with no effect on proliferation or apoptosis of FRTL-AQP4 cells and primary astrocytes. Permeability assays indicated that geraldol did not alter the water transport function of AQP4 in either cell system. The present study suggests the potential therapeutic value of geraldol for NMO drug development.

Abnormal Baseline Brain Activity in Neuromyelitis Optica Patients Without Brain Lesion Detected by Resting-State Functional Magnetic Resonance Imaging

OBJECTIVE

To investigate the baseline brain activity in neuromyelitis optica patients without brain lesion using the regional amplitude of low-frequency fluctuation (ALFF) and fractional amplitude of low-frequency fluctuation (fALFF) as indexes.

MATERIALS AND METHODS

Forty-two patients of NMO with normal performance in conventional MRI and 42 healthy controls, matched in gender and age, were enrolled in this study. Resting-state functional magnetic resonance imaging (rs-fMRI) data acquired using the rs-fMRI Data Analysis Toolkit. The relationships between expanded disability states scale (EDSS) scores, abnormal baseline brain activity and disease duration were explored.

RESULTS

The left inferior temporal, left cerebellum_4_5, bilateral superior temporal pole, left caudate, right superior temporal, left middle frontal and left superior occipital showed significantly increased ALFF in the NMO. Regions of abnormal fALFF were similar to those of ALFF except that increased fALFF were also indicated in the right cerebellum crus2, right hippocampus, left parahippocampal gyrus and left supplementary motor area. Furthermore, a significant correlation between EDSS scores and ALFF/fALFF was noted in the left inferior temporal gyrus.

CONCLUSION

Results confirmed the disturbances in NMO-related neural networks, which probably be related to spinal cord damage.

Comprehensive review of neuromyelitis optica and clinical characteristics of neuromyelitis optica patients in Puerto Rico

Neuromyelitis optica (NMO) is an immune-mediated inflammatory disorder of the central nervous system. It is characterized by concurrent inflammation and demyelination of the optic nerve (optic neuritis [ON]) and the spinal cord (myelitis). Multiple studies show variations in prevalence, clinical, and demographic features of NMO among different populations. In addition, ethnicity and race are known as important factors on disease phenotype and clinical outcomes. There are little data on information about NMO patients in underserved groups, including Puerto Rico (PR). In this research, we will provide a comprehensive overview of all aspects of NMO, including epidemiology, environmental risk factors, genetic factors, molecular mechanism, symptoms, comorbidities and clinical differentiation, diagnosis, treatment, its management, and prognosis. We will also evaluate the demographic features and clinical phenotype of NMO patients in PR. This will provide a better understanding of NMO and establish a basis of knowledge that can be used to improve care. Furthermore, this type of population-based study can distinguish the clinical features variation among NMO patients and will provide insight into the potential mechanisms that cause these variations.

Evolving Landscape of Multiple Sclerosis in India: Challenges in the Management

Multiple sclerosis (MS) is a chronic neurological disease which often leads to disability. The complex etiology and progressive nature pose challenges in the management of patients with MS, particularly in developing countries like India. Lack of data on prevalence further complicates estimation of the magnitude of MS in India. There are various other challenges associated with management of patients with MS due to which the therapy is utilized by only a small segment of population in India. This article encapsulates the gaps and challenges in the management of patients with MS and presents suggestions and recommendations of the members of advisory boards held to discuss these challenges. The advisory board members suggested that an early diagnosis of MS and an early initiation of treatment are essential to achieve better results for tackling MS-related challenges. In addition, awareness and education about MS among people, regular training to physicians, emphasis on the use of revised 2010 McDonald criteria, and utilization of advanced diagnostic modalities in magnetic resonance imaging would help to achieve desirable as well as effective therapeutic outcomes. Further, access to an easy-to-use therapy delivery system could also be beneficial in attaining an adequate treatment adherence and related health benefits.

Role of low plasma volume treatment on clinical efficacy of plasmapheresis in neuromyelitis optica

BACKGROUND:

Neuromyelitis optica (NMO) is an autoimmune demyelinating disease preferentially targeting the optic nerves and spinal cord. Plasmapheresis (PP) is an effective adjunct therapy in severe NMO attacks. The recommended minimum plasma volume to be treated per session of PP is equivalent to total plasma volume (TPV) of the patient.

AIM:

To study the effect of lower plasma volume treated in patients with NMO on clinical efficacy of plasmapheresis in comparison to minimum recommended volume.

METHODS:

This retrospective study was done on acute NMO patients who were managed with PP at our center. Patients who had 5 sessions of PP, spread over 10 days, were included. Clinical outcome was defined as per predefined criteria.

RESULTS:

24 patients who underwent PP for acute NMO met our inclusion criteria. Females (age; mean (SD) 33.7 (11.2) years) were more common (n = 18). The minimum recommended plasma volume (PV) that was supposed to be treated per patient during entire acute therapeutic period was 195.5 (14.6) mL per kilogram-body-weight (kg-bw). We treated lower plasma volume (mean (SD) 112.7 (17.0) mL per kg-bw); the difference was significant (P < 0.05). The volume treated was same across the gender (P > 0.05). Significant clinical improvement was observed in 79% of patients (n = 19) after 6 months. There were no significant differences in volume of plasma treated, between patients who had moderate and marked improvement; also, who did, and did not have significant clinical improvement (P > 0.05; for both).

CONCLUSIONS:

Plasmapheresis is a safe and efficient add-on therapy in NMO, especially in steroid-resistant cases. Although the volumes of plasma treated during acute plasmapheresis were less than recommended minimum volumes, majority of patients had significant clinical improvement.

Antibodies from multiple sclerosis patients preferentially recognize hyperglucosylated adhesin of non-typeable Haemophilus influenzae

In autoimmune diseases, there have been proposals that exogenous “molecular triggers”, i.e., specific ‘non-self antigens’ accompanying infectious agents, might disrupt control of the adaptive immune system resulting in serious pathologies. The etiology of multiple sclerosis (MS) remains unclear. However, epidemiologic data suggest that exposure to infectious agents may be associated with increased MS risk and progression may be linked to exogenous, bacterially-derived, antigenic molecules, mimicking mammalian cell surface glycoconjugates triggering autoimmune responses. Previously, antibodies specific to a gluco-asparagine (N-Glc) glycopeptide, CSF114(N-Glc), were identified in sera of an MS patient subpopulation. Since the human glycoproteome repertoire lacks this uniquely modified amino acid, we turned our attention to bacteria, i.e., Haemophilus influenzae, expressing cell-surface adhesins including N-Glc, to establish a connection between H. influenzae infection and MS. We exploited the biosynthetic machinery from the opportunistic pathogen H. influenzae (and the homologous enzymes from A. pleuropneumoniae) to produce a unique set of defined glucosylated adhesin proteins. Interestingly we revealed that a hyperglucosylated protein domain, based on the cell-surface adhesin HMW1A, is preferentially recognized by antibodies from sera of an MS patient subpopulation. In conclusion the hyperglucosylated adhesin is the first example of an N-glucosylated native antigen that can be considered a relevant candidate for triggering pathogenic antibodies in MS.

Neuromyelitis optica with hypothalamic involvement

We describe two cases of neuromyelitis optica (NMO) with clinical and radiographically confirmed features of hypothalamic involvement, in the absence of other parenchymal brain lesions. Their course is otherwise typical of Devic’s form of NMO. A review of the literature identifies additional cases of NMO in which clinical features attributable to under-recognized dysfunction of the hypothalamic-pituitary axis were present. We propose that the currently accepted criteria for the diagnosis of NMO could be revisited to recognize the possibility of lesions developing within hypothalamic structures.

Therapy of NMO spectrum disorders

Neuromyelitis optica (NMO) is an autoimmune demyelinating condition of the central nervous system often associated with aquaporin-4 (AQP4) autoantibodies manifesting as severe optic neuritis and long segment myelitis with tendency to relapse. Seronegative patients and who do not meet the NMO criteria are classified as having NMO Spectrum Disorder (NMOSD), but are treated identically to clinically definite NMO. Acute relapse is treated with intravenous methylprednisolone for 5 days with or without subsequent treatment with plasma exchange (PE). This must be followed by oral steroid to prevent rebound worsening and further relapse. For relapse prevention, immunosuppressive agents that have been found to be effective are azathioprine, rituximab, mycophenolate mofetil, methotrexate, and mitoxantrone; although none of which have been validated in randomized, controlled trial. Some patients do relapse with monotherapy, and switching to more effective agent or use of combination therapy is beneficial in such situation. There is no consensus about the duration of preventive therapy, but generally 2-3 years of relapse-free period is considered the minimum, taking into account the risks of long-term toxicity of these agents.

The Fc Receptor-Like 3 Polymorphisms (rs7528684, rs945635, rs3761959 and rs2282284) and The Risk of Neuromyelitis Optica in A Chinese Population

Neuromyelitis optica (NMO) appears to be a severe inflammatory demyelinating disease occurring in the central nervous system. Furthermore, the Fc receptor-like 3 (FCRL3) gene was previously found to be susceptible for a certain inflammatory demyelinating diseases (such as multiple sclerosis). The present study, therefore, was aimed to explore the possible association of FCRL3 gene polymorphisms with susceptibility to NMO in a Chinese Han population. Seven single nucleotide polymorphisms (SNPs) of FCRL3 were, respectively, genotyped in 132 NMO patients and 264 healthy controls via PCR assay. Moreover, the t-test and the chi-square test were used to estimate the association between genetic mutations of FCRL3 and the risk of NMO with Statistical Analysis System (SAS) software (Version 9.0). It was demonstrated that FCRL3_3, 5, 6 and 8, SNPs were remarkably associated with susceptibility to NMO in both allelic [OR = 1.50 (95% CI: 1.11-2.03, P = 0.008), OR = 1.44 (1.07-1.94, P = 0.015), OR = 1.45 (1.08-1.95, P = 0.014), and OR = 2.01 (1.13-3.60, P = 0.016)] and homozygous models [OR = 2.19 (95% CI: 1.19-3.99, P = 0.010), OR = 2.09 (1.15-3.80, P = 0.014), OR = 2.04 (1.13-3.67, P = 0.016), and OR = 5.33 (1.02-27.9, P = 0.027)]. However, the other 4 SNPs, FCRL3_4, FCRL3_7, FCRL3_9, did not show the significant associations with NMO. Conclusions in the present study could be drawn that 4 SNPs in FCRL3 (FCRL3_3*C, 5*C, 6*A, 8*G) might account for increased risk of NMO in a Chinese-Han population. Nevertheless, further cohort studies are in demand to validate the association in the future.

Clinical manifestations of neuromyelitis optica in male and female patients

Neuromyelitis optica (NMO) is a severe, idiopathic, immuno-mediated, inflammatory demyelinating disease of the central nervous system. We examined the clinical features between male and female NMO patients, for which not much data exist. One hundred and eight Chinese Han patients with NMO were analysed retrospectively, all had been detected for the aquaporin-4 (AQP4) antibody using a cell-based assay. Of 108 NMO patients, 92 were female and 16 were male (female/male = 5.75). Ninety-four (87%) were positive for the AQP4 antibody in their serum and/or cerebral spinal fluid. Aquaporin-4 antibody-positive NMO patients had a higher female/male ratio than the negative group (P = 0.001). Female NMO patients had a higher positive rate of the AQP4 antibody than male NMO patients (92.4 vs 56.3%, P = 0.001). All NMO male patients were divided according to their AQP4 antibody status. 77.8% (7/9) of patients in the seropositive group had initial optic neuritis, while only one patient (14.3%, 1/7) in the negative group had optic neuritis (P = 0.041). Limb paraesthesia was reported in only one patient in the negative group (11.1%), but it was reported in all patients in the positive group (100%) (P = 0.001). The mean length of vertebral segments of the spinal cord lesions was 3.6 ± 1.3 in the positive group, while it was 6.6 ± 2.6 in the negative group (P < 0.0001). The involvement of the cervical spinal cord was found in 88.9% (8/9) of the positive members, but only 11.1% in the negative group (P = 0.009). However, the involvement of the thoracic spinal cord was found in 22.2% of patients in the positive group and 85.7% of patients in the negative members (P = 0.041). In conclusion, male NMO is rare and has a low positive rate of AQP4 antibody.

Assessment of Optic Nerve Impairment in Patients with Neuromyelitis Optica by MR Diffusion Tensor Imaging

BACKGROUND

Diffusion tensor imaging (DTI) has been used for the evaluation of the white matter integrity. In this study, we evaluated optic nerve impairment in patients with neuromyelitis optica (NMO) using DTI.

METHODOLOGY/PRINCIPAL FINDINGS

Optic nerve DTI were performed on 28 NMO patients and 38 normal controls. Fractional anisotropy (FA) values were measured in the anterior, middle, and posterior parts of the intraorbital optic nerve segment. For the posterior intraorbital optic nerve, FA values of BI (0.20±0.07), MI (0.24±0.16), and NA (0.25±0.14) decreased significantly compared with that of NC (0.43±0.07) (P<0.05), and ROC analysis demonstrated that the area under the curve (AUC) measurements for BI vs. NC, MI vs. NC, NA vs. NC, and NMO (including BI, MI, and NA) vs. NC were 0.99, 0.93, 0.88, and 0.96, respectively. The corresponding diagnostic sensitivities of ROC analysis were 100%, 80%, 80%, and 91%; and the specificities were 93%, 97%, 91%, and 93%.

CONCLUSIONS/SIGNIFICANCE

Decreased FA value in the intraorbital optic nerve, especially in the posterior part of the nerve, was demonstrated as a characteristic MR feature for NMO-related optic nerve impairment.

No Overlap among Serum GAD65, NMDAR and AQP4 Antibodies in Patients with Neuromyelitis Optica Spectrum Disorders

OBJECTIVE

To evaluate whether serum glutamic acid decarboxylase (GAD), N-methyl-D-aspartate-receptor (NMDAR), and aquaporin-4 (AQP4) autoantibodies coexist in patients with neuromyelitis optica (NMO)/NMO spectrum disorders (NMOSD).

METHODS

Serum samples were collected from 98 patients with NMO/NMOSD. Serum GAD65, NMDAR and AQP4 antibodies were measured using a cell-based assay.

RESULTS

A total of 63 patients (64.3%) had myelitis and optic neuritis and satisfied the revised diagnostic criteria for NMO. Longitudinally extensive transverse myelitis was seen on spinal cord magnetic resonance imaging, showing continuous T2-weighted signal abnormalities in at least three vertebral segments in 26 patients (26.5%); 5 patients (5.1%) had recurrent optic neuritis, and 4 patients (4.1%) had brain syndromes with optic neuritis and myelitis. None of the 98 patients had diabetes, stiff-man syndrome, or epilepsy. All 98 patients tested positive for AQP4 antibody. No patients tested positive for GAD65 and NMDAR antibodies.

CONCLUSIONS

In the present study, we found no simultaneous presence of serum GAD65, NMDAR and AQP4 antibodies in patients with NMO/NMOSD.

Serum anticardiolipin antibodies in patients with neuromyelitis optica spectrum disorder

The presence of anticardiolipin antibodies (ACLA) in multiple sclerosis (MS) patients has been reported, but there are some debates on the relationship between ACLA and MS. We assessed the clinical features of neuromyelitis optica spectrum disorders (NMOSD) patients with ACLA. A consecutive cohort of 480 subjects with NMOSD (n = 70), MS (n = 90) and control (n = 220) were analysed retrospectively. Patients' serum was tested by a dot-immunogold filtration assay for the presence of ACLA-IgG, IgM and IgA antibodies. In MS patients, 5 (5.6 %) of the 90 patients showed ACLA-IgG reactivity in the serum. In NMOSD patients, 32 (45.7 %) of the 70 patients showed ACLA reactivity in the serum, among which ACLA-IgG seropositivity was 45.7 % (32/70), ACLA-IgG + IgM seropositivity was 8.6 % (6/70), and ACLA-IgG + IgA seropositivity was 4.3 % (3/70). NMOSD patients were higher in ACLA-IgG (p < 0.0001) and ACLA-IgG + IgM (p = 0.006) than the MS patients. NMOSD patients had higher ACLA-IgG than the control patients (p < 0.0001). In comparison with the controls, the MS patients were lower in ACLA for IgG (p = 0.014) and IgM (p = 0.004). Seropositive ACLA patients increased in age (p = 0.013) and had higher D-dimer levels (DD) (p = 0.002) than the seronegative NMOSD patients. Furthermore, positive ACLA-IgG + IgM patients were increased in age (p = 0.001), had higher baseline EDSS (p = 0.001), antithrombin III activity (p = 0.04), and DD levels (p = 0.005) than the pure positive ACLA-IgG NMOSD patients. Patients with NMOSD had more occurrences of ACLA than patients with MS. NMOSD patients with positive ACLA-IgG + IgM had a worse outcome that may be associated with elder age and abnormal coagulation parameters in blood.

Serum thyroid-stimulating hormone and anti-thyroglobulin antibody are independently associated with lesions in spinal cord in central nervous system demyelinating diseases

Transverse myelitis (TM) is associated with neuromyelitis optica (NMO) and multiple sclerosis (MS). Early recognition of useful parameters may be helpful to distinguish their difference. This retrospective study analyzed thyroid parameters from 243 serum samples (relapse = 128; remission = 115) of 178 patients with demyelinating diseases (NMO, n = 25; TM, n = 48; MS, n = 105). The relationship between thyroid and clinical parameters was analyzed. Patients with NMO and TM had a higher frequency of abnormal thyroid-stimulating hormone (TSH), anti-thyroglobulin antibodies (TG-Ab), and antithyroid peroxidase antibody (TPO-Ab) than MS patients (p<0.05). The level of TSH and TG-Ab returned to normal levels after administration of high-dose intravenous methylprednisolone (p<0.05). In 96 patients (NMO, n = 19; TM, n = 25; MS, n = 52) without treatment, serum levels of TSH, TG-Ab and TPO-Ab were significantly different between patients with and without myelitis (p<0.01). Patients positive for aquaporin-4 (AQP4) antibodies showed higher abnormalities of TSH (p = 0.001), TG-Ab (p = 0.004) and TPO-Ab (p<0.0001) levels than AQP4 antibodies negative patients. Logistic regression analyses revealed independent relationships between TSH (odds ratio [OR]  = 33.994; p<0.0001), TG-Ab (OR = 7.703; p = 0.017) and myelitis occurrence in 96 patients at the active stage. In 52 MS patients experiencing their first attack, MS patients with myelitis were associated with TSH abnormalities (OR = 42.778; p<0.0001). This study showed increased abnormalities of thyroid parameters in patients with NMO and TM than in MS patients. MS patients with myelitis also had greater TSH abnormality than in MS patients without myelitis. Abnormal TSH and TG-Ab were independently associated with myelitis occurrence in central nervous system demyelinating disorders.

Novel advances in the diagnosis and treatment of neuromyelitis optica: is there a need to redefine the gold standard?

Neuromyelitis optica (NMO) is an inflammatory disease of the central nervous system characterized by severe attacks of optic neuritis and myelitis and, unlike multiple sclerosis, was initially thought to spare the brain in the early stages. The term NMO spectrum disorder (NMOSD) was recently used to qualify restricted forms of the disorder, which include recurrent optic neuritis, relapsing transverse myelitis and some encephalitic/brainstem presentations associated with positive aquaporin4 antibodies. It was also recently found that other immunological targets such as myelin oligodendrocyte glycoprotein (MOG) may be associated with seronegative NMO patients. In the present study, we detail the moving concept of NMOSD from the recent years and propose some therapeutic strategies that are clearly different compared with multiple sclerosis treatment.

Neuromyelitis optica (Devic's syndrome)

Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the central nervous system that selectively targets the optic nerve and spinal cord, although it may also target certain areas of the brain. The majority of cases are associated with relapses. A specific biomarker, an autoantibody that targets aquaporin-4, is present in the majority of patients and facilitates the diagnosis. Detection of this biomarker in serum has enabled recognition of an expanded spectrum of clinical disorders that previously would not have met diagnostic criteria for NMO. Aquaporin-4 IgG1 autoantibodies are pathogenic and produce lesions of the brain when injected intracerebrally or systemically. The clinical course of NMO is dominated by acute attacks. Progressive worsening of disability, as occurs in prototypic multiple sclerosis, is distinctly unusual. Corticosteroids and plasma exchange are useful for management of acute attacks. Several treatments used to prevent attacks of multiple sclerosis are ineffective in this condition; effective immunotherapies include azathioprine, mycophenolate mofetil and rituximab.

Antineutrophil cytoplasmic antibodies in patients with idiopathic inflammatory-demyelinating diseases

OBJECTIVE

We assessed the clinical significance of antineutrophil cytoplasm antibodies (ANCA) in patients with idiopathic inflammatory-demyelinating disease (IIDD).

METHODS

A consecutive cohort of 269 subjects with IIDD and 595 controls was analyzed retrospectively.

RESULTS

Among all subjects, ANCA positivity rates were low [9.5% in a perinuclear pattern (pANCA) and 2.3% in a cytoplasmic pattern (cANCA)]. One of the 117 patients with multiple sclerosis (MS) had cANCA and 2 had pANCA. Ten patients with neuromyelitis optica (NMO; 13.9%) had pANCA and 3 (4.2%) had cANCA. Four patients with recurrent longitudinal extensive transverse myelitis (RLETM; 19.0%) had pANCA and 1 (4.8%) had cANCA. In monophasic TM, 22.9% were pANCA seropositive. Among patients with brainstem syndromes, 14.3% were pANCA seropositive. Patients with NMO, RLETM or monophasic TM had higher pANCA levels than patients with MS. There was a positive association between spinal cord (SC) lesions and ANCA, and especially between longitudinal extensive transverse myelitis and ANCA. Among anti-aquaporin 4 antibody-positive patients, ANCA-positive patients (n = 16) were older and had higher Expanded Disability Status Scale scores, more antinuclear antibodies, longer SC lesions and fewer brain abnormalities than the ANCA-negative patients (n = 68). In the NMO subgroup, ANCA-positive patients were older and had more antinuclear antibodies and longer SC lesions than ANCA-negative patients.

CONCLUSION

Among the IIDDs, we found a higher occurrence of ANCA in patients with NMO spectrum disorders than in patients with MS. Therefore, ANCA is another interesting marker of autoimmunity in IIDD patients, especially those with anti-aquaporin 4 antibody.

Relapsing optic neuritis: a multicentre study of 62 patients

Background:

Optic neuritis (ON) may be the first symptom of a central nervous system demyelinating, systemic or infectious disease but few patients experience recurrent episodes and have a negative workup.

Objective:

This disorder, named relapsing optic neuritis (RON), is poorly described in the literature and still presents a particular challenge in diagnosis and management.

Methods:

We describe the clinical, laboratory, magnetic resonance imaging (MRI) and disability course of RON in a French cohort of 62 patients, based on a multicentre, retrospective, observational study.

Results:

In our cohort, we identified two distinct groups of RON patients. The first is characterised by relapsing inflammatory optic neuritis (RION, 68%), which is non-progressive, whereas the second presented as a chronic relapsing inflammatory optic neuritis (CRION, 32%), which is progressive. We have noted more cases with steroid dependence in the CRION group than the RION group (42% vs 10%). The long-term visual prognosis was more severe in CRION patients and neuromyelitis optica-immunoglobulin G (NMO-IgG)-positive patients.

Conclusion:

RON is likely a separate entity corresponding to an autoimmune disease that differs from multiple sclerosis (MS), NMO and vasculitis. We provide a new classification system based on a better understanding of RON which could allow an improved management by early treatment of poor prognosis forms.

Serum analysis by 1H nuclear magnetic resonance spectroscopy: a new tool for distinguishing neuromyelitis optica from multiple sclerosis

BACKGROUND

Neuromyelitis optica (NMO) and multiple sclerosis (MS), two inflammatory demyelinating diseases, are characterized by different therapeutic strategies. Currently, the only biological diagnostic tool available to distinguish NMO from MS is the specific serum autoantibody that targets aquaporin 4, but its sensitivity is low.

OBJECTIVE

To assess the diagnostic accuracy of metabolomic biomarker profiles in these two neurological conditions, compared to control patients.

METHODS

We acquired serum spectra (47 MS, 44 NMO and 42 controls) using proton nuclear magnetic resonance ((1)H-NMR) spectroscopy. We used multivariate pattern recognition analysis to identify disease-specific metabolic profiles.

RESULTS

The (1)H-NMR spectroscopic analysis evidenced two metabolites, originating probably from astrocytes, scyllo-inositol and acetate, as promising serum biomarkers of MS and NMO, respectively. In 87.8% of MS patients, scyllo-inositol increased 0.15 to 3-fold, compared to controls and in 74.3% of NMO patients, acetate increased 0.4 to 7-fold, compared to controls. Using these two metabolites simultaneously, we can discriminate MS versus NMO patients (sensitivity, 94.3%; specificity, 90.2%).

CONCLUSION

This study demonstrates the potential of (1)H-NMR spectroscopy of serum as a novel, promising analytical tool to discriminate populations of patients affected by NMO or MS.

Distinct serum cytokine profiles in neuromyelitis optica and multiple sclerosis

Multiple sclerosis (MS) is the most common prototypic inflammatory demyelinating disease. Neuromyelitis optica (NMO) is another inflammatory demyelinating disease of the central nervous system that exhibits clinical symptoms mainly associated with optic neuritis and myelopathy. The inflammatory reaction in MS is associated with an upregulation of a variety of T helper 1 (Th1)- or Th17-mediated cytokines. However, NMO and MS are intertwined both clinically and pathologically, which complicates their diagnosis and treatment. The aim of this study was to evaluate the differences in serum cytokine levels in patients with NMO and MS. We collected peripheral serum from patients with these central nervous system demyelinating diseases for the study. A cytometric bead array was used to assess the cytokine levels using flow cytometry. We found more inflammatory [interleukin (IL)-2 and interferon-γ) and anti-inflammatory (IL-4 and IL-10) cytokines in NMO than in MS. The differences in the optimal cutoff points of serum cytokines, including IL-2 ≥5 pg/mL, can differentiate NMO from MS. In conclusion, patients with NMO had an increased Th1-mediated inflammatory response, but similar Th17-mediated inflammation changes compared to patients with MS. Serum cytokine studies can differentiate NMO cases from MS.

Progressive necrotizing myelopathy: part of the spectrum of neuromyelitis optica?

This case series reviews the clinical, radiographic and laboratory findings of five patients with progressive idiopathic myelopathy with evidence of cord necrosis who presented in our institution over a 5 year period ending in May 2005. Patients fulfilling the following criteria were included: (1) presentation with myelopathy without overt visual involvement at initial presentation; (2) demonstration with magnetic resonance imaging (MRI) of contiguously abnormal signal in the spinal cord spanning at least three vertebral segments without evidence of arteriovenous malformation or significant disk disease; (3) absence of systemic disease or neoplasm. All patients were women, identified themselves as African American and were older than 35 years. Pain was reported at initial presentation in four cases. The distinctive feature was a relapsing course with intervening variable improvement of function and progression to quadriplegia in less than 4 years. An increased IgG index and/or oligoclonal banding was detected in two patients. The leukocyte count in the cerebrospinal fluid (CSF) was elevated in all cases but in only one specimen did the count exceed 50 cells. None of the patients initially had clinical signs of an optic neuropathy but unilaterally prolonged visual evoked potentials were present in one individual who went on to developed optic neuritis 19 months after the first clinical presentation. Another patient developed optic neuritis 45 months after disease onset. Immunomodulatory and plasma exchange therapy were of some benefit at least early in the course but the disease progressed despite these interventions. Neuromyelitis optica (NMO)-IgG antibody, a serum or CSF marker described in individuals with classic NMO and optico-spinal multiple sclerosis (MS), was present in all cases. On the basis of shared clinical and imaging features in the cord, progressive necrotizing myelopathy observed in this case series exhibits key features of a limited form of NMO (Devic's disease) and opticospinal MS. The presence of NMO-IgG antibody marker suggests that progressive necrotizing myelopathy is part of a disease spectrum of which traditional NMO is a select presentation.

Antibodies target microvessels in neuromyelitis optica and multiple sclerosis patients

OBJECTIVE

This study investigated the presence of serum antibodies targeting microvessels in Chinese patients with multiple sclerosis (MS) and neuromyelitis optica (NMO).

METHODS

Serum samples were collected from 50 patients with NMO, 10 with longitudinally extensive transverse myelitis (LETM), 4 with recurrent optic neuritis, 42 with MS and 27 controls. Serum antibodies binding to microvessels were measured by indirect immunofluorescence (IIF) assay of tissue sections from the brain, stomach and pancreas, and human umbilical vein endothelial cells (HUVEC). Aquaporin-4 (AQP4) antibodies were detected using a cell-based assay.

RESULTS

Indirect immunofluorescence assay of tissue sections from 42 samples (30.4%, 42/138) were positive for microvessel antibodies, where microvessel antibody positivity was 38% (19/50) in patients with NMO, 57.1% (8/14) in high-risk NMO (hrNMO), 26.2% (11/42) in MS, and 14.8% (4/27) in controls. Based on HUVEC analysis, 14 patients with NMO (28%, 14/50), 5 with hrNMO (35.7%, 5/14), 15 with MS (35.7%, 15/42), and 5 controls (18.5%, 5/27) had (AECA). Sixteen patients (32%, 16/50) with NMO, four with hrNMO (28.6%, 4/14), two with MS (4·8%, 2/42), and 0% of controls were positive for antinuclear antibodies (ANA). In MS patients, seropositive AECA MS patients had higher numbers of relapse events and increased spinal lesions than seronegative MS patients (P < 0.05).

CONCLUSIONS

Serum microvessel antibodies were present in patients with NMO and MS and the role of microvessel antibodies in diseases may be heterogeneous. This study suggests that AECA may have some significance in MS patients.

Evaluation of clinical interest of anti-aquaporin-4 autoantibody followup in neuromyelitis optica

Neuromyelitis optica (NMO) is an autoimmune disease in which a specific biomarker named NMO-IgG and directed against aquaporin-4 (AQP4) has been found. A correlation between disease activity and anti-AQP4 antibody (Ab) serum concentration or complement-mediated cytotoxicity has been reported, but the usefulness of longitudinal evaluation of these parameters remains to be evaluated in actual clinical practice. Thirty serum samples from 10 NMO patients positive for NMO-IgG were collected from 2006 to 2011. Anti-AQP4 Ab serum concentration and complement-mediated cytotoxicity were measured by flow cytometry using two quantitative cell-based assays (CBA) and compared with clinical parameters. We found a strong correlation between serum anti-AQP4 Ab concentration and complement-mediated cytotoxicity (P < 0.0001). Nevertheless, neither relapse nor worsening of impairment level was closely associated with a significant increase in serum Ab concentration or cytotoxicity. These results suggest that complement-mediated serum cytotoxicity assessment does not provide extra insight compared to anti-AQP4 Ab serum concentration. Furthermore, none of these parameters appears closely related to disease activity and/or severity. Therefore, in clinical practice, serum anti-AQP4 reactivity seems not helpful as a predictive biomarker in the followup of NMO patients as a means of predicting the onset of a relapse and adapting the treatment accordingly.

Monoclonal antibodies in neuroinflammatory diseases

INTRODUCTION

Monoclonal antibodies (mAbs) represent an emerging and rapidly growing field of therapy in neuroinflammatory diseases. Adhesion molecule blockade by natalizumab represents the first approved mAb therapy in neurology, approved for therapy of highly active multiple sclerosis (MS). Removal of immune cells by anti-CD52 mAb alemtuzumab or anti-CD20 mAb rituximab are other prime examples with existing positive Phase II and Phase III trials. MS clearly represents the neuroinflammatory disease entity with the largest body of evidence. However, some of these approaches are currently investigated or translated for use in other, rare neuroinflammatory diseases, such as neuromyelitis optica (NMO), inflammatory neuropathies and (neuro)-muscular disorders.

AREAS COVERED

This review will highlight the most relevant therapeutic approaches involving mAbs in the field of neuroinflammatory diseases as published in peer-reviewed journals and presented on international meetings.

EXPERT OPINION

There is continuously growing evidence on the therapeutic relevance of mAbs in neuroinflammatory disorders. In MS meanwhile several studies have provided evidence for efficacy: In addition to natalizumab, approved in 2006, several other candidates are under development, the most eminent examples with the most advanced study programs being anti-CD52 alemtuzumab, anti-CD20 principles and anti-CD25 daclizumab. Other intriguing candidates are anti-IL-17 strategies, and interference with the complement pathway, partly also developed for other neuroinflammatory disorders.

Helicobacter pylori infection in Neuromyelitis Optica and Multiple Sclerosis

OBJECTIVE

To determine the Helicobacter pylori infection status in patients with multiple sclerosis (MS) and neuromyelitis optica (NMO) spectrum.

METHODS

H. pylori infection was certified by indirect immunofluorescence assay. Aquaporin-4 (AQP4) antibody was detected by cell-based assay. H. pylori seroprevalence was measured in 118 patients with NMO (n = 52), high-risk NMO (hrNMO, longitudinally extensive transverse myelitis, n = 17 and recurrent optic neuritis, n = 7), MS (n = 42) and healthy controls (n = 27). Logistic regression analysis was used to determine associations between H. pylori infection and NMO and MS.

RESULTS

H. pylori antibodies were present in 119 serum samples (82.1%, 119/145), with antibody positivity in 90.4% (47/52) of the patients with NMO, 95.8% (23/24) of the patients with hrNMO, 73.8% (31/42) of the patients with MS and 59.3% (16/27) of the controls. NMO spectrum patients had greater positivity for H. pylori than MS patients (p < 0.05) and controls (p < 0.05). The frequency of H. pylori seropositivity did not significantly differ between MS patients and controls (p = 0.726). H. pylori seropositivity was significantly higher in AQP4 antibody-positive patients (54/58, 93.1%; p = 0.038) than in AQP4 antibody-negative patients (48/60, 80%). Logistic regression analysis showed that H. pylori seropositivity was significantly associated with hrNMO [odds ratio (OR) = 9.311, p = 0.005] or hrNMO + NMO (OR = 6.350, p = 0.028).

CONCLUSION

H. pylori infection was present in most Chinese patients with NMO and hrNMO, and may be a risk factor for the NMO spectrum.

Immunological follow-up of patients with neuromyelitis optica: Is there a good biomarker?

A serial assessment of biomarkers related to disease activity could be clinically useful in some autoimmune diseases. Neuromyelitis optica (NMO) is a severe inflammatory disease of the optic nerves and spinal cord that can be associated with lupus erythematosus, Sjögren syndrome or myasthenia gravis. In this review, we discuss the existing data on the use of biomarkers of disease activity in NMO. A specific and pathogenic antibody (Ab) directed against aquaporin 4 (AQP4) was recently discovered in this disease. The relapses were frequently accompanied by a rise and immunosuppressive therapy by a decrease in serum anti-AQP4 Ab concentrations. However, this association is not strong enough to justify treatment changes based only on anti-AQP4 Ab level variations. This parameter might be helpful as a longitudinal biomarker but only if a threshold inducing a relapse and justifying a switch in therapy can be established. A link between disease severity and serum cytotoxicity against AQP4-expressing cells was proposed but has not yet been confirmed. Finally, the assessment of T cell immunity against AQP4 and specific cytokines could be future directions for research.

Idiopathic transverse myelitis and neuromyelitis optica: clinical profiles, pathophysiology and therapeutic choices

Transverse myelitis is a focal inflammatory disorder of the spinal cord which may arise due to different etiologies. Transverse myelitis may be idiopathic or related/secondary to other diseases including infections, connective tissue disorders and other autoimmune diseases. It may be also associated with optic neuritis (neuromyelitis optica), which may precede transverse myelitis. In this manuscript we review the pathophysiology of different types of transverse myelitis and neuromyelitis optica and discuss diagnostic criteria for idiopathic transverse myelitis and risk of development of multiple sclerosis after an episode of transverse myelitis. We also discuss treatment options including corticosteroids, immunosuppressives and monoclonal antibodies, plasma exchange and intravenous immunoglobulins.

Neuromyelitis optica: an antibody-mediated disorder of the central nervous system

Neuromyelitis optica (NMO) is a recurrent inflammatory disease that preferentially targets the optic nerves and spinal cord leading to blindness and paralysis. The hallmarks of NMO include bilateral optic neuritis and longitudinally extensive transverse myelitis. Woman and African Americans are overrepresented in the US patient population. NMO is associated with the NMO-IgG biomarker, which targets the aquaporin-4 water channel on astrocytes. The humoral pathology of NMO lesions include IgG and IgM deposits and infiltration by granulocytes suggesting that the NMO-IgG may be involved in the pathogenesis of disease. This review of the recent NMO literature covers the clinical features, epidemiology, radiology and pathology of disease and includes discussion of the important basic science research work in the field.

Neuromyelitis optica immunoglobulin G in Chinese patients detected by immunofluorescence assay on a monkey brain substrate

BACKGROUND

Serum neuromyelitis optica immunoglobulin G (NMO-IgG) is used as a biomarker to differentiate between neuromyelitis optica (NMO) and multiple sclerosis (MS). However, the original assay is expensive and complex and shows low sensitivity. Here, we investigated the potential of NMO-IgG detection using an indirect immunofluorescence (IIF) assay on monkey brains.

METHODS

NMO-IgG seroprevalence was determined in 168 samples by an IIF assay on a monkey brain substrate. The data were compared with those from a standard mouse brain IIF assay using McNemar and kappa tests.

RESULTS

Thirty-one of 50 (62%) NMO patients, 7 of 18 (38.9%) longitudinally extensive transverse myelitis patients, 6 of 57 (10.5%) MS patients, and 5 of 10 (50%) optic neuritis patients were seropositive for NMO-IgG. None of the acute partial transverse myelitis patients (n = 3) or healthy controls (n = 20) was positive. Thus, the sensitivity of the test was 62% for the patients with clinically definite NMO. The specificity was 89.5%, considering the 57 MS patients as the control group. The modified IIF assay on monkey brains and the standard IIF assay based on mouse brains were not significantly different (McNemar test; p = 1.000). The two assays were concordant in 39 seropositive samples and 100 seronegative samples (kappa test; kappa = 0.592, p < 0.0001).

CONCLUSIONS

Although the modified IIF monkey brain assay was no better than the standard mouse brain IIF assay, we affirmed that NMO-IgG is a sensitive and specific biomarker to differentiate between NMO and MS.

Aquaporin 4 antibodies in the cerebrospinal fluid are helpful in diagnosing Chinese patients with neuromyelitis optica

OBJECTIVE

It was the aim of this study to compare the diagnostic efficiency of anti-aquaporin 4 (AQP4) antibody detection between serum and cerebrospinal fluid (CSF) samples in Chinese patients with central nervous system demyelinating diseases.

METHODS

Anti-AQP4 antibodies were detected by a cell-based assay. We calculated the sensitivity, specificity and coherence in 118 patients with neuromyelitis optica (NMO, n = 39), multiple sclerosis (n = 34), longitudinally extensive transverse myelitis (LETM, n = 22), optic neuritis (ON, n = 6), opticospinal multiple sclerosis (n = 8) and acute partial transverse myelitis (n = 9).

RESULTS

Forty-four serum samples (33.8%) were positive for anti-AQP4 antibodies. Anti-AQP4 antibody seropositivity was 76.9, 59.1 and 16.7% in patients with NMO, LETM and ON, respectively. Sixty-five CSF samples (50%) were positive for anti-AQP4 antibodies. Anti-AQP4 antibody positivity was 87.1, 81.8, 83.3, 62.5 and 11.8% in patients with NMO, LETM, ON, opticospinal multiple sclerosis and multiple sclerosis, respectively. The κ value of the coherence test was 0.585 (p < 0.0001) between the two types of samples. The antibody positivity rate was significantly different between the two body fluids (p = 0.0008, McNemar test). The sensitivity and specificity were 74.3 and 100% in serum, 85.7 and 88.2% in CSF, and 94.3 and 88.2% for serum and CSF combined, respectively.

CONCLUSION

The sensitivity of anti-AQP4 antibodies in the CSF was higher than that in the serum, and their combined use is helpful in diagnosing Chinese patients with NMO.