Comparison of live and fixed cell-based assay performance: implications for the diagnosis of MOGAD in a low-middle income country

Background

Though considered optimal, live cell-based assay (LCBA) is often unavailable for the diagnosis of myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD) in resource-poor regions. This study was undertaken to determine the agreement between LCBA and the widely available fixed cell-based assay (FCBA), for recommending testing guidelines within our region.

Method

All consecutive patients in our registry with a MOGAD phenotype were tested. The results from a commercially available FCBA (Euroimmun, Germany) were compared with a validated "in-house" LCBA. Clinical and MRI data were available for correlation.

Results

Among the 257 patient samples tested, 118 (45.9%) were positive by FCBA titre ≥1: 10 and or LCBA titres ≥1: 160 titre and 139 samples were negative. There was robust agreement between the two assays (agreement 98.8%, Cohen's kappa 0.98 [95% CI- 0.95-1.00], Spearman correlation 0.97 (p < 0.0001). Among five discordant samples, four had clinical and or MRI data which supported an alternate diagnosis. There was a modest correlation between assay titres, particularly for samples with titres ≥ 1:100 in FCBA (Spearman's Rho 0.26, p 0.005). Thirty samples were positive by FCBA at < 1:100 titre and included 1:80 (20),1:40(7) and 1:10 (3) titres. Among them, 80% had clear positive titres when tested by LCBA.

Conclusion

The FCBA tested with serum dilutions of 1:10 was highly predictive of MOGAD in our study and compared well with our "in-house" LCBA. The current recommendations for testing at higher dilutions need to be re-examined in light of our findings. The results of our study should ideally be replicated in a larger dataset but at the same time provide some guidance for the accurate diagnosis of MOGAD in resource-poor settings.

International Delphi Consensus on the Management of AQP4-IgG+ NMOSD: Recommendations for Eculizumab, Inebilizumab, and Satralizumab

BACKGROUND AND OBJECTIVES

Neuromyelitis optica spectrum disorder (NMOSD) is a rare debilitating autoimmune disease of the CNS. Three monoclonal antibodies were recently approved as maintenance therapies for aquaporin-4 immunoglobulin G (AQP4-IgG)-seropositive NMOSD (eculizumab, inebilizumab, and satralizumab), prompting the need to consider best practice therapeutic decision-making for this indication. Our objective was to develop validated statements for the management of AQP4-IgG-seropositive NMOSD, through an evidence-based Delphi consensus process, with a focus on recommendations for eculizumab, inebilizumab, and satralizumab.

METHODS

We recruited an international panel of clinical experts in NMOSD and asked them to complete a questionnaire on NMOSD management. Panel members received a summary of evidence identified through a targeted literature review and provided free-text responses to the questionnaire based on both the data provided and their clinical experience. Responses were used to generate draft statements on NMOSD-related themes. Statements were voted on over a maximum of 3 rounds; participation in at least 1 of the first 2 rounds was mandatory. Panel members anonymously provided their level of agreement (6-point Likert scale) on each statement. Statements that failed to reach a predefined consensus threshold (≥67%) were revised based on feedback and then voted on in the next round. Final statements were those that met the consensus threshold (≥67%).

RESULTS

The Delphi panel comprised 24 experts, who completed the Delphi process in November 2021 after 2 voting rounds. In round 1, 23/25 statements reached consensus and were accepted as final. The 2 statements that failed to reach consensus were revised. In round 2, both revised statements reached consensus. Twenty-five statements were agreed in total: 11 on initiation of or switching between eculizumab, inebilizumab, and satralizumab; 3 on monotherapy/combination therapy; 7 on safety and patient population considerations; 3 on biomarkers/patient-reported outcomes; and 1 on research gaps.

DISCUSSION

An established consensus method was used to develop statements relevant to the management of AQP4-IgG-seropositive NMOSD. These international statements will be valuable for informing individualized therapeutic decision-making and could form the basis for standardized practice guidelines.

Helicobacter pylori infection may influence prevalence and disease course in myelin oligodendrocyte glycoprotein antibody associated disorder (MOGAD) similar to MS but not AQP4-IgG associated NMOSD

Background

Helicobacter pylori (Hp) persists after colonizing the gut in childhood, and potentially regulates host immune system through this process. Earlier studies have shown that Hp infection in childhood, may protect against MS in later life. Such an association was not seen with AQP4-IgG positive NMOSD, while the association with MOGAD is unclear.

Objective

To evaluate frequency of Hp IgG among patients with MOGAD, MS, NMOSD and matched controls and its effect on disease course. To ascertain whether childhood socio economic factors were linked to prevalence of Hp infection.

Methods

In all, 99 patients diagnosed to have MOGAD, 99 AQP4 IgG+ NMOSD, 254MS and 243 matched controls were included. Patient demographics, diagnosis, age at disease onset, duration and the last recorded expanded disability status scale (EDSS) were obtained from our records. Socioeconomic and educational status was queried using a previously validated questionnaire. Serum HpIgG was detected using ELISA kits (Vircell, Spain).

Result

Frequency of Hp IgG was significantly lower among MOGAD (28.3% vs 44%, p-0.007) and MS (21.2% vs 44%, p-0.0001) but not AQP4-IgG+ NMOSD patients (42.4% vs 44%, p-0.78) when compared to controls. Frequency of Hp IgG in MOGAD & MS patients combined (MOGAD-MS) was significantly lower than those with NMOSD (23.2% vs 42.4%, p- 0.0001). Seropositive patients with MOGAD- MS were older (p-0.001. OR -1.04, 95% CI- 1.01- 1.06) and had longer disease duration (p- 0.04, OR- 1.04, 95% CI- 1.002- 1.08) at time of testing. Educational status was lower among parents/caregivers of this study cohort (p- 0.001, OR -2.34, 95% CI- 1.48-3.69) who were Hp IgG+.

Conclusions

In developing countries Hp infection may be a significant environmental factor related to autoimmune demyelinating CNS disease. Our preliminary data suggests that Hp may exert a differential influence - a largely protective role for MS-MOGAD but not NMOSD and may influence disease onset and course. This differential response maybe related to immuno-pathological similarities between MOGAD and MS in contrast to NMOSD. Our study further underscores the role of Hp as a surrogate marker for poor gut hygiene in childhood and its association with later onset of autoimmune diseases.

Diagnosis of myelin oligodendrocyte glycoprotein antibody-associated disease: International MOGAD Panel proposed criteria

Serum antibodies directed against myelin oligodendrocyte glycoprotein (MOG) are found in patients with acquired CNS demyelinating syndromes that are distinct from multiple sclerosis and aquaporin-4-seropositive neuromyelitis optica spectrum disorder. Based on an extensive literature review and a structured consensus process, we propose diagnostic criteria for MOG antibody-associated disease (MOGAD) in which the presence of MOG-IgG is a core criterion. According to our proposed criteria, MOGAD is typically associated with acute disseminated encephalomyelitis, optic neuritis, or transverse myelitis, and is less commonly associated with cerebral cortical encephalitis, brainstem presentations, or cerebellar presentations. MOGAD can present as either a monophasic or relapsing disease course, and MOG-IgG cell-based assays are important for diagnostic accuracy. Diagnoses such as multiple sclerosis need to be excluded, but not all patients with multiple sclerosis should undergo screening for MOG-IgG. These proposed diagnostic criteria require validation but have the potential to improve identification of individuals with MOGAD, which is essential to define long-term clinical outcomes, refine inclusion criteria for clinical trials, and identify predictors of a relapsing versus a monophasic disease course.

Diagnostic value of intereye difference metrics for optic neuritis in aquaporin-4 antibody seropositive neuromyelitis optica spectrum disorders

BACKGROUND

The novel optic neuritis (ON) diagnostic criteria include intereye differences (IED) of optical coherence tomography (OCT) parameters. IED has proven valuable for ON diagnosis in multiple sclerosis but has not been evaluated in aquaporin-4 antibody seropositive neuromyelitis optica spectrum disorders (AQP4+NMOSD). We evaluated the diagnostic accuracy of intereye absolute (IEAD) and percentage difference (IEPD) in AQP4+NMOSD after unilateral ON >6 months before OCT as compared with healthy controls (HC).

METHODS

Twenty-eight AQP4+NMOSD after unilateral ON (NMOSD-ON), 62 HC and 45 AQP4+NMOSD without ON history (NMOSD-NON) were recruited by 13 centres as part of the international Collaborative Retrospective Study on retinal OCT in Neuromyelitis Optica study. Mean thickness of peripapillary retinal nerve fibre layer (pRNFL) and macular ganglion cell and inner plexiform layer (GCIPL) were quantified by Spectralis spectral domain OCT. Threshold values of the ON diagnostic criteria (pRNFL: IEAD 5 µm, IEPD 5%; GCIPL: IEAD: 4 µm, IEPD: 4%) were evaluated using receiver operating characteristics and area under the curve (AUC) metrics.

RESULTS

The discriminative power was high for NMOSD-ON versus HC for IEAD (pRNFL: AUC 0.95, specificity 82%, sensitivity 86%; GCIPL: AUC 0.93, specificity 98%, sensitivity 75%) and IEPD (pRNFL: AUC 0.96, specificity 87%, sensitivity 89%; GCIPL: AUC 0.94, specificity 96%, sensitivity 82%). The discriminative power was high/moderate for NMOSD-ON versus NMOSD-NON for IEAD (pRNFL: AUC 0.92, specificity 77%, sensitivity 86%; GCIP: AUC 0.87, specificity 85%, sensitivity 75%) and for IEPD (pRNFL: AUC 0.94, specificity 82%, sensitivity 89%; GCIP: AUC 0.88, specificity 82%, sensitivity 82%).

CONCLUSIONS

Results support the validation of the IED metrics as OCT parameters of the novel diagnostic ON criteria in AQP4+NMOSD.

The Acute Optic Neuritis Network (ACON): Study protocol of a non-interventional prospective multicenter study on diagnosis and treatment of acute optic neuritis

Optic neuritis (ON) often occurs at the presentation of multiple sclerosis (MS), neuromyelitis optica spectrum disorders (NMOSD), and myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD). The recommended treatment of high-dose corticosteroids for ON is based on a North American study population, which did not address treatment timing or antibody serostatus. The Acute Optic Neuritis Network (ACON) presents a global, prospective, observational study protocol primarily designed to investigate the effect of time to high-dose corticosteroid treatment on 6-month visual outcomes in ON. Patients presenting within 30 days of the inaugural ON will be enrolled. For the primary analysis, patients will subsequently be assigned into the MS-ON group, the aquapotin-4-IgG positive ON (AQP4-IgG+ON) group or the MOG-IgG positive ON (MOG-IgG+ON) group and then further sub-stratified according to the number of days from the onset of visual loss to high-dose corticosteroids (days-to-Rx). The primary outcome measure will be high-contrast best-corrected visual acuity (HC-BCVA) at 6 months. In addition, multimodal data will be collected in subjects with any ON (CIS-ON, MS-ON, AQP4-IgG+ON or MOG-IgG+ON, and seronegative non-MS-ON), excluding infectious and granulomatous ON. Secondary outcomes include low-contrast best-corrected visual acuity (LC-BCVA), optical coherence tomography (OCT), magnetic resonance imaging (MRI) measurements, serum and cerebrospinal fluid (CSF) biomarkers (AQP4-IgG and MOG-IgG levels, neurofilament, and glial fibrillary protein), and patient reported outcome measures (headache, visual function in daily routine, depression, and quality of life questionnaires) at presentation at 6-month and 12-month follow-up visits. Data will be collected from 28 academic hospitals from Africa, Asia, the Middle East, Europe, North America, South America, and Australia. Planned recruitment consists of 100 MS-ON, 50 AQP4-IgG+ON, and 50 MOG-IgG+ON. This prospective, multimodal data collection will assess the potential value of early high-dose corticosteroid treatment, investigate the interrelations between functional impairments and structural changes, and evaluate the diagnostic yield of laboratory biomarkers. This analysis has the ability to substantially improve treatment strategies and the accuracy of diagnostic stratification in acute demyelinating ON.

Trial registration

ClinicalTrials.gov, identifier: NCT05605951.

Diagnosis and classification of optic neuritis

There is no consensus regarding the classification of optic neuritis, and precise diagnostic criteria are not available. This reality means that the diagnosis of disorders that have optic neuritis as the first manifestation can be challenging. Accurate diagnosis of optic neuritis at presentation can facilitate the timely treatment of individuals with multiple sclerosis, neuromyelitis optica spectrum disorder, or myelin oligodendrocyte glycoprotein antibody-associated disease. Epidemiological data show that, cumulatively, optic neuritis is most frequently caused by many conditions other than multiple sclerosis. Worldwide, the cause and management of optic neuritis varies with geographical location, treatment availability, and ethnic background. We have developed diagnostic criteria for optic neuritis and a classification of optic neuritis subgroups. Our diagnostic criteria are based on clinical features that permit a diagnosis of possible optic neuritis; further paraclinical tests, utilising brain, orbital, and retinal imaging, together with antibody and other protein biomarker data, can lead to a diagnosis of definite optic neuritis. Paraclinical tests can also be applied retrospectively on stored samples and historical brain or retinal scans, which will be useful for future validation studies. Our criteria have the potential to reduce the risk of misdiagnosis, provide information on optic neuritis disease course that can guide future treatment trial design, and enable physicians to judge the likelihood of a need for long-term pharmacological management, which might differ according to optic neuritis subgroups.

COVID-19 infection and vaccination against COVID- 19: Impact on managing demyelinating CNS disorders in Southern India- Experience from a demyelinating disease registry

Background and objective

The impact of COVID-19 infection and the effect of COVID-19 vaccinations on patients with demyelinating central nervous system disease in low middle income countries (LMIC's) have not been reported in detail earlier. We sought to identify risk factors associated with COVID-19 infection and the role of vaccination in order to develop management guidelines relevant to our patients.

Methods

A total of 621 patients from our registry that included 297 MS and 324 non MS disorders (Aquaporin- 4 antibody positive [50], Myelin oligodendrocyte glycoprotein antibody positive [81], seronegative [162] and clinically isolated syndrome [31]) were contacted. COVID-19 infection and vaccination status were queried. Patients who self reported COVID-19 infection based on a positive RT PCR report were compared with non infected patients to identify factors associated with susceptibility for COVID-19 infection. Univariate and multivariate analysis of potential risk factors included demographic and clinical features, body mass index (BMI), presence of comorbidities, absolute lymphocyte count, treatment types and vaccination status.

Results

Sixty seven patients with MS and 27 with non MS disorders developed COVID-19 infection. Among them 81 patients had mild infection and remained quarantined at home. All 13 patients who needed hospitalization recovered. Vaccination status was known in 582 patients among whom 69.8% had completed or taken one dose of vaccine at the time of inquiry. Majority of treated patients (61.3%) were on nonspecific immunosuppressants. In univariate analysis, presence of ≥1 comorbidity was significantly associated with COVID-19 infection in both MS (p value 0.01, OR-2.28, 95%CI- 1.18–4.4) and non MS patients (p- 0.001, OR-4.4, 95% CI-1.88–10.24). In the latter, BMI ≥ 30 (p-0.04, OR-3.27, 95% CI- 0.98–10.87) and EDSS score ≥ 3 (p-0.02, OR- 2.59,95% CI- 1.08–6.23) were other significant associations. History of prior COVID-19 vaccination was associated with reduced frequency of COVID-19 infection among MS (p- 0.001,OR- 0.24,95% CI- 0.13–0.43) and non MS patients (p- 0.0001,OR-0.14, 95% CI- 0.058–0.35). In multivariate analysis presence of comorbidities significantly increased and prior vaccination significantly reduced frequency of COVID-19 infection for both MS and related disorders. Concurrent disease modifying treatments showed a trend for association with infection. In the unvaccinated group, patients on disease modifying treatment were significantly at risk of infection, 81.5% unvaccinated and treated versus 18.5% who were unvaccinated and untreated (p- 0.0001, OR-10.1, 95% CI-0.56–2.11).

Conclusion

Frequency and severity of COVID-19 infection was low among our patient cohort. Higher rate of infection in the treated group was significantly seen among unvaccinated patients. Our preliminary results suggests that in LMIC's, where “off label therapies” with inexpensive immunosuppressives are the main disease modifying drugs, mRNA vaccinations appear safe and effective against severe COVID-19 infection.

Longitudinal retinal changes in MOGAD

OBJECTIVE

Patients with myelin oligodendrocyte glycoprotein antibody (MOG-IgG) associated disease (MOGAD) suffer from severe optic neuritis (ON) leading to retinal neuro-axonal loss, which can be quantified by optical coherence tomography (OCT). We assessed whether ON-independent retinal atrophy can be detected in MOGAD.

METHODS

Eighty MOGAD patients and 139 healthy controls (HC) were included. OCT data was acquired with 1) Spectralis spectral domain OCT (MOGAD (N=66) and HC (N=103)) and 2) Cirrus HD-OCT (MOGAD (N=14) and HC (N=36)). Macular combined ganglion cell and inner plexiform layer (GCIPL) and peripapillary retinal nerve fibre layer (pRNFL) were quantified.

RESULTS

At baseline, GCIPL and pRNFL were lower in MOGAD eyes with a history of ON (MOGAD-ON) compared with MOGAD eyes without a history of ON (MOGAD-NON) and HC (p<0.001). MOGAD-NON eyes had lower GCIPL volume compared to HC (p<0.001) in the Spectralis, but not in the Cirrus cohort. Longitudinally (follow-up up to 3 years), MOGAD-ON with ON within the last 6-12 months before baseline exhibited greater pRNFL thinning than MOGAD-ON with an ON >12 months ago (p<0.001). The overall MOGAD cohort did not exhibit faster GCIPL thinning compared with HC.

INTERPRETATION

Our study suggests the absence of attack-independent retinal damage in MOGAD. Yet, ongoing neuroaxonal damage or oedema resolution seems to occur for up to 12 months after ON, which is longer than what has been reported with other ON forms. These findings support that the pathomechanisms underlying optic nerve involvement and the evolution of OCT retinal changes after ON is distinct in MOGAD. This article is protected by copyright. All rights reserved.

The risk of infections for multiple sclerosis and neuromyelitis optica spectrum disorder disease-modifying treatments: Eighth European Committee for Treatment and Research in Multiple Sclerosis Focused Workshop Review. April 2021

Over the recent years, the treatment of multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) has evolved very rapidly and a large number of disease-modifying treatments (DMTs) are now available. However, most DMTs are associated with adverse events, the most frequent of which being infections. Consideration of all DMT-associated risks facilitates development of risk mitigation strategies. An international focused workshop with expert-led discussions was sponsored by the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) and was held in April 2021 to review our current knowledge about the risk of infections associated with the use of DMTs for people with MS and NMOSD and corresponding risk mitigation strategies. The workshop addressed DMT-associated infections in specific populations, such as children and pregnant women with MS, or people with MS who have other comorbidities or live in regions with an exceptionally high infection burden. Finally, we reviewed the topic of DMT-associated infectious risks in the context of the current SARS-CoV-2 pandemic. Herein, we summarize available evidence and identify gaps in knowledge which justify further research.

Astrocytic outer retinal layer thinning is not a feature in AQP4-IgG seropositive neuromyelitis optica spectrum disorders

BACKGROUND

Patients with anti-aquaporin-4 antibody seropositive (AQP4-IgG+) neuromyelitis optica spectrum disorders (NMOSDs) frequently suffer from optic neuritis (ON) leading to severe retinal neuroaxonal damage. Further, the relationship of this retinal damage to a primary astrocytopathy in NMOSD is uncertain. Primary astrocytopathy has been suggested to cause ON-independent retinal damage and contribute to changes particularly in the outer plexiform layer (OPL) and outer nuclear layer (ONL), as reported in some earlier studies. However, these were limited in their sample size and contradictory as to the localisation. This study assesses outer retinal layer changes using optical coherence tomography (OCT) in a multicentre cross-sectional cohort.

METHOD

197 patients who were AQP4-IgG+ and 32 myelin-oligodendrocyte-glycoprotein antibody seropositive (MOG-IgG+) patients were enrolled in this study along with 75 healthy controls. Participants underwent neurological examination and OCT with central postprocessing conducted at a single site.

RESULTS

No significant thinning of OPL (25.02±2.03 µm) or ONL (61.63±7.04 µm) were observed in patients who were AQP4-IgG+ compared with patients who were MOG-IgG+ with comparable neuroaxonal damage (OPL: 25.10±2.00 µm; ONL: 64.71±7.87 µm) or healthy controls (OPL: 24.58±1.64 µm; ONL: 63.59±5.78 µm). Eyes of patients who were AQP4-IgG+ (19.84±5.09 µm, p=0.027) and MOG-IgG+ (19.82±4.78 µm, p=0.004) with a history of ON showed parafoveal OPL thinning compared with healthy controls (20.99±5.14 µm); this was not observed elsewhere.

CONCLUSION

The results suggest that outer retinal layer loss is not a consistent component of retinal astrocytic damage in AQP4-IgG+ NMOSD. Longitudinal studies are necessary to determine if OPL and ONL are damaged in late disease due to retrograde trans-synaptic axonal degeneration and whether outer retinal dysfunction occurs despite any measurable structural correlates.

Overcoming the challenges in diagnosis of AQP4-IgG positive neuromyelitis optica spectrum disorders in resource poor settings using an indigenized and cost effective cell based assay

BACKGROUND

Diagnosis of neuromyelitis optica spectrum disorders (NMOSD) in India is hindered by limited access to cost effective and sensitive assays for detection of aquaporin-4 antibody (AQP4-IgG) in India.

OBJECTIVE

To develop a cost effective, sensitive, cell based assay (CBA) for detection of AQP4-IgG and to evaluate the serological status in patients with NMOSD diagnosed by 2015 diagnostic criteria.

METHOD

Stably transfected Chinese hamster ovary (CHO) cell line expressing aquaporin M23 isomer was established. A fixed CBA was developed and validated in 381 samples including clinically definite NMOSD (n = 87), high risk NMOSD (n = 51), other demyelinating disorders (n = 92), other neurological disorders (n = 51) and healthy volunteers (n = 100). We tested the same samples again using a commercially available CBA and compared the results. All assays were performed by 2 independent investigators blinded to clinical and serological status.

RESULTS

Our "in house"(Mangalore) assay showed sensitivity of 81.6% (95% CI 71.86-89.11%) for clinically definite NMOSD and 29.41% (95% CI 17.50-43.8%) for high risk NMOSD. Specificity was 100% for both groups. Both assays showed similar results for 67/ 87 (77.01%) patients with definite NMOSD while 4 samples tested positive by our assay alone (Cohen's kappa coefficient [K] - 0.86). Among the high risk group 14/51 (27.5%) samples showed similar results, one patient additionally was positive by the Mangalore assay (K - 0.95).

Retinal Optical Coherence Tomography in Neuromyelitis Optica

Background and Objectives

To determine optic nerve and retinal damage in aquaporin-4 antibody (AQP4-IgG)-seropositive neuromyelitis optica spectrum disorders (NMOSD) in a large international cohort after previous studies have been limited by small and heterogeneous cohorts.

Methods

The cross-sectional Collaborative Retrospective Study on retinal optical coherence tomography (OCT) in neuromyelitis optica collected retrospective data from 22 centers. Of 653 screened participants, we included 283 AQP4-IgG–seropositive patients with NMOSD and 72 healthy controls (HCs). Participants underwent OCT with central reading including quality control and intraretinal segmentation. The primary outcome was thickness of combined ganglion cell and inner plexiform (GCIP) layer; secondary outcomes were thickness of peripapillary retinal nerve fiber layer (pRNFL) and visual acuity (VA).

Results

Eyes with ON (NMOSD-ON, N = 260) or without ON (NMOSD-NON, N = 241) were assessed compared with HCs (N = 136). In NMOSD-ON, GCIP layer (57.4 ± 12.2 μm) was reduced compared with HC (GCIP layer: 81.4 ± 5.7 μm, p < 0.001). GCIP layer loss (−22.7 μm) after the first ON was higher than after the next (−3.5 μm) and subsequent episodes. pRNFL observations were similar. NMOSD-NON exhibited reduced GCIP layer but not pRNFL compared with HC. VA was greatly reduced in NMOSD-ON compared with HC eyes, but did not differ between NMOSD-NON and HC.

Discussion

Our results emphasize that attack prevention is key to avoid severe neuroaxonal damage and vision loss caused by ON in NMOSD. Therapies ameliorating attack-related damage, especially during a first attack, are an unmet clinical need. Mild signs of neuroaxonal changes without apparent vision loss in ON-unaffected eyes might be solely due to contralateral ON attacks and do not suggest clinically relevant progression but need further investigation.

Evaluating the Role of HLA DRB1 Alleles and Oligoclonal Bands in Influencing Clinical Course of Multiple Sclerosis - A Study from the Mangalore Demyelinating Disease Registry

Background:

The possible interaction between genetic and immunological factors in influencing clinical course of multiple sclerosis (MS) has not been studied previously in Indian population.

Aim:

In this study we evaluated the association of HLA alleles and OCB in affecting clinical course and disability of MS.

Methods:

Clinical and demographic features of 145 MS patients who had CSF oligoclonal bands (OCB) tested by isoelectric focussing technique were analyzed, disability status estimated, and HLA DRB1 alleles were genotyped.

Results:

OCBs were positive in 53.8% (78/145) of all MS cases. Patients with CSF OCB had more frequent relapses and an association with HLA DRB1*15. Early disease onset and a high annualized relapse rate was associated with HLA DRB1*03 allele. A relapsing remitting course for MS was seen with HLA DRB1*03 & 15 while a progressive disease was associated with DRB1*01. Presence of both OCB and HLA DRB1*13 was significantly associated with disability in this cohort.

Conclusion:

The results of our study suggest that an interaction between immunological and genetic factors may influence disease onset, course, and disability in MS.

Role of Viral Infections in Multiple Sclerosis Pathogenesis among Indian Population

Background

The role of viral infections in multiple sclerosis (MS) pathogenesis is unclear.

Objective

Certain neurotropic viruses previously linked with MS among white population were studied including Epstein-Barr virus, human herpesvirus-6 (HHV-6) and MS-associated retrovirus (MSRV).

Material and Methods

Sixty-two MS patients (37 had a recent clinical relapse) and 65 controls with other neurological disorders were included. Blood and cerebrospinal fluid (CSF) samples were obtained and processed with the primary objective of determining whether there was intrathecal multiplication of viruses under study (EBV, HHV6 A and B and human endogenous retrovirus) or a breach in blood-brain barrier associated with viral presence in both peripheral blood and CSF.

Results

Evidence of breach in blood-brain barrier was seen in 86.5% of patients as evidenced by abnormal CSF/serum albumin index and or MRI. EBV nuclear antigen (EBNA1 IgG) was seen in 89% of MS patients and 58% controls (P = <0.001). However, HHV6 IgG was similar in both groups (85% versus 81%; P = 0.45). In affinity immunoblotting reaction intrathecal IgG synthesis against EBNA1 antigen was demonstrable in 26% (16/62) of patients and none against HHV6. A subset of patients showed significant elevation in mean copy number of plasma EBV DNA during relapse and there was a trend for the same among patients harboring HHV-6B. No evidence of isolated intrathecal viral presence or multiplication was seen.

Conclusions

The results of our study suggest that viruses studied namely EBV and HHV6 have a role in triggering relapses through a peripheral mechanism, rather than a direct role through intrathecal multiplication.

Asian and African/Caribbean AQP4-NMOSD patient outcomes according to self-identified race and place of residence

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune astrocytopathy characterized by aquaporin-4 antibodies, whose prognosis is influenced by onset age, race, environmental exposures and immunosuppression. Distinguishing the contribution of environment from genetics is challenging. We aimed to compare neuromyelitis optica spectrum disorder (NMOSD) patient outcomes according to self-identified racial group and place of residence.

METHODS

This retrospective analysis of prospectively collected data included non-white anti-aquaporin-4 antibody positive NMOSD patients under follow-up from 15 centers [United Kingdom, France, Germany, Denmark, Martinique, United States of America, Japan, South Korea, Singapore, Thailand, China (including Hong Kong) and India]. Racial groups were designated: African/Caribbean; South Asian; East Asian (including Southeast Asia). Patients from these racial groups residing outside Africa/Caribbean or Asia were compared with those living in the Caribbean or the Asian areas. Kaplan-Meier survival curves and Cox models were generated using time to sustained Expanded Disability Status Scale≥6.0 or death; time to sustained Kurtzke Visual Function Score≥3.0 or a composite endpoint of all three.

RESULTS

Among 821 patients, African/Caribbean patients (n = 206) had the shortest time to immunosuppression and higher visual disability at onset. South Asian patients (n = 65) were younger, had lower visual disability at onset and higher mortality rate. East Asians (n = 550) had the lowest relapse rate and lowest accrued motor disability. Survival analysis of African/Caribbean outside Africa/Caribbean vs those in the Caribbean showed a significant difference in the composite endpoint (p = 0.024,log-rank test), not apparently related to treatment differences. No significant differences between native and those residing outside Asia were found for other racial groups.

CONCLUSION

This NMOSD study reports the effects of place of residence on the outcomes in different races. Place of residence may not be a significant driver of disability among Asian patients, while it may influence African/Caribbean patient outcomes. Validating these findings could help distinguish between genetic causes and potentially modifiable environmental factors.

Clostridium bolteae is elevated in neuromyelitis optica spectrum disorder in India and shares sequence similarity with AQP4

OBJECTIVE

To understand the role of gut microbiome in influencing the pathogenesis of neuromyelitis optica spectrum disorders (NMOSDs) among patients of south Indian origin.

METHODS

In this case-control study, stool and blood samples were collected from 39 patients with NMOSD, including 17 with aquaporin 4 IgG antibodies (AQP4+) and 36 matched controls. 16S ribosomal RNA (rRNA) sequencing was used to investigate the gut microbiome. Peripheral CD4+ T cells were sorted in 12 healthy controls, and in 12 patients with AQP4+ NMOSD, RNA was extracted and immune gene expression was analyzed using the NanoString nCounter human immunology kit code set.

RESULTS

Microbiota community structure (beta diversity) differed between patients with AQP4+ NMOSD and healthy controls (p < 0.001, pairwise PERMANOVA test). Linear discriminatory analysis effect size identified several members of the microbiota that were altered in patients with NMOSD, including an increase in Clostridium bolteae (effect size 4.23, p 0.00007). C bolteae was significantly more prevalent (p = 0.02) among patients with AQP4-IgG+ NMOSD (n = 8/17 subjects) compared with seronegative patients (n = 3/22) and was absent among healthy stool samples. C bolteae has a highly conserved glycerol uptake facilitator and related aquaporin protein (p59-71) that shares sequence homology with AQP4 peptide (p92-104), positioned within an immunodominant (AQP4 specific) T-cell epitope (p91-110). Presence of C bolteae correlated with expression of inflammatory genes associated with both innate and adaptive immunities and particularly involved in plasma cell differentiation, B cell chemotaxis, and Th17 activation.

CONCLUSION

Our study described elevated levels of C bolteae associated with AQP4+ NMOSD among Indian patients. It is possible that this organism may be causally related to the immunopathogenesis of this disease in susceptible individuals.

Coexistence of autoantibodies and other autoimmune diseases with multiple sclerosis and related disorders – Experience from the Mangalore demyelinating disease registry (MANDDIR)

Background:

Co-occurrence of other autoimmune disorders (AID) and autoantibodies in patients with autoimmune demyelinating CNS disorders have not been studied previously in patients of Indian origin.

Objective:

To determine the frequency of concomitant autoimmune disorders, anti-nuclear antibody (ANA) and antithyroid antibody (ATAb) and to evaluate the impact on clinical course of disease.

Materials and Methods:

A total of 111 patients with MS and 152 patients with non-MS demyelinating disorders were included. Demographics, clinical course and disability were recorded. History of other autoimmune disorders (AIDs) in patients and first degree relatives was noted. Serum ANA and ATAb were tested.

Results:

Concomitant AIDs were seen in 21% of MS and 19% of non-MS patients. Autoimmune thyroid disease was most frequent and seen in 10.8% of MS and 6.6% of non-MS disorders. Frequency of ATAb was significantly higher among MS group (MS 25.5% vs non-MS 13.2% P = 0.04) but that of ANA was similar between the 2 groups (MS 19.8% vs non-MS 26.9% P = 0.17). A positive family history of autoimmune disorders was noted in 20% of MS and 15.1% of non-MS disorders. Clinical course was unaffected by presence of concomitant AID and autoantibodies.

Conclusion:

Cooccurrence of autoantibodies and AID are seen in a significant number of patients with MS and non-MS disorders and influences clinical management.

Cohort profile: a collaborative multicentre study of retinal optical coherence tomography in 539 patients with neuromyelitis optica spectrum disorders (CROCTINO)

PURPOSE

Optical coherence tomography (OCT) captures retinal damage in neuromyelitis optica spectrum disorders (NMOSD). Previous studies investigating OCT in NMOSD have been limited by the rareness and heterogeneity of the disease. The goal of this study was to establish an image repository platform, which will facilitate neuroimaging studies in NMOSD. Here we summarise the profile of the Collaborative OCT in NMOSD repository as the initial effort in establishing this platform. This repository should prove invaluable for studies using OCT to investigate NMOSD.

PARTICIPANTS

The current cohort includes data from 539 patients with NMOSD and 114 healthy controls. These were collected at 22 participating centres from North and South America, Asia and Europe. The dataset consists of demographic details, diagnosis, antibody status, clinical disability, visual function, history of optic neuritis and other NMOSD defining attacks, and OCT source data from three different OCT devices.

FINDINGS TO DATE

The cohort informs similar demographic and clinical characteristics as those of previously published NMOSD cohorts. The image repository platform and centre network continue to be available for future prospective neuroimaging studies in NMOSD. For the conduct of the study, we have refined OCT image quality criteria and developed a cross-device intraretinal segmentation pipeline.

FUTURE PLANS

We are pursuing several scientific projects based on the repository, such as analysing retinal layer thickness measurements, in this cohort in an attempt to identify differences between distinct disease phenotypes, demographics and ethnicities. The dataset will be available for further projects to interested, qualified parties, such as those using specialised image analysis or artificial intelligence applications.

Treatment of MOG-IgG-associated disorder with rituximab: An international study of 121 patients

OBJECTIVE

To assess the effect of anti-CD20 B-cell depletion with rituximab (RTX) on relapse rates in myelin oligodendrocyte glycoprotein antibody-associated disorder (MOGAD).

METHODS

Retrospective review of RTX-treated MOGAD patients from 29 centres in 13 countries. The primary outcome measure was change in relapse rate after starting rituximab (Poisson regression model).

RESULTS

Data on 121 patients were analysed, including 30 (24.8%) children. Twenty/121 (16.5%) were treated after one attack, of whom 14/20 (70.0%) remained relapse-free after median (IQR) 11.2 (6.3-14.1) months. The remainder (101/121, 83.5%) were treated after two or more attacks, of whom 53/101 (52.5%) remained relapse-free after median 12.1 (6.3-24.9) months. In this 'relapsing group', relapse rate declined by 37% (95%CI=19-52%, p<0.001) overall, 63% (95%CI=35-79%, p = 0.001) when RTX was used first line (n = 47), and 26% (95%CI=2-44%, p = 0.038) when used after other steroid-sparing immunotherapies (n = 54). Predicted 1-year and 2-year relapse-free survival was 79% and 55% for first-line RTX therapy, and 38% and 18% for second-/third-line therapy. Circulating CD19+B-cells were suppressed to <1% of total circulating lymphocyte population at the time of 45/57 (78.9%) relapses.

CONCLUSION

RTX reduced relapse rates in MOGAD. However, many patients continued to relapse despite apparent B-cell depletion. Prospective controlled studies are needed to validate these results.

Consensus Statement On Immune Modulation in Multiple Sclerosis and Related Disorders During the COVID-19 Pandemic: Expert Group on Behalf of the Indian Academy of Neurology

Knowledge related to SARS-CoV-2 or 2019 novel coronavirus (2019-nCoV) is still emerging and rapidly evolving. We know little about the effects of this novel coronavirus on various body systems and its behaviour among patients with underlying neurological conditions, especially those on immunomodulatory medications. The aim of the present consensus expert opinion document is to appraise the potential concerns when managing our patients with underlying CNS autoimmune demyelinating disorders during the current COVID-19 pandemic.

No Evidence of Disease Activity (NEDA) in Multiple Sclerosis - Shifting the Goal Posts

A combined endpoint measure to define no evidence of disease activity (NEDA) is becoming increasingly appealing in the treatment of multiple sclerosis (MS). Initial efforts using a 3 parameter NEDA monitored disease activity using clinical and MRI lesion data. Later refinements, introduced more recently, include brain atrophy measurement and cognitive function analysis in defining NEDA-4. Using these stringent criteria clearly differentiated the usefulness of different disease modifying agents (DMDs) in achieving and sustaining NEDA over time. This in turn has changed attitudes and strategies in management of MS.

289 MRI abnormalities in mog antibody disease

Aims

To analyse the MRI abnormalities of myelin oligodendrocyte glycoprotein-antibody (MOG-Ab) associated demyelinating disease.

Methods

Clinical records and 165 MRIs from 56 patients with MOG-Abs were reviewed.

Results

The median age was 29(8–71) years and 52% percent were female. Common phenotypes included isolated optic neuritis (ON)=17, or transverse myelitis (TM)=16, ON+TM =12, and combinations of above groups with cerebral and/or brainstem involvement=11. Seventeen patients (30%) fulfilled NMOSD 2015 diagnostic criteria.

All patients had brain imaging and 89% (50/56) had spinal imaging. Common areas of MRI brain abnormality involved brainstem(32%), hemispheric white matter(29%), corticospinal tracts(21%), and U-fibres(20%). Dawson’s fingers were not detected in any patients.

Cord imaging showed longitudinally extensive myelitis in 69% (20/29) and atrophy in 4% (2/47). Optic nerve imaging was abnormal in 69% (18/26) of patients, with bilateral lesions in 33% and long lesions (orbital and/or canalicular) in 83%.

On serial MRI, radiological improvement was observed in 76% (22/29; median interval- 14 months) and importantly asymptomatic new lesions were absent in 13 untreated patients after a median of 16.5 months.

Conclusions

Apart from optic nerve and spinal cord changes, brainstem and hemispheric white matter abnormalities are common in MOG-antibody disease. Irrespective of treatment, asymptomatic accrual of brain and/or spinal lesions is uncommon.

MOG-IgG-associated disease has a stereotypical clinical course, asymptomatic visual impairment and good treatment response

Objectives

We investigated the clinical characteristics and treatment response in myelin oligodendrocyte glycoprotein antibody (MOG-IgG)-associated disease and looked for evidence of subclinical disease.

Methods

We prospectively evaluated the frequency and pattern of relapse, tested afferent visual function and monitored treatment response in 42 south Asian patients from a single centre.

Results

Eighteen patients (42.9%) had monophasic and 24 (57.1%) a relapsing course. Disease duration was longer (P<0.02) in those with a relapsing course. Median time to the second attack was prolonged (P<0.04) in patients with recurrent transverse myelitis when compared with neuromyelitis optica spectrum disorder and recurrent optic neuritis. Thirteen out of 17 patients (76.5%) initially presenting with optic neuritis developed recurrent optic neuritis later. After the first attack of transverse myelitis, 17 out of 22 (77.3%) had disease confined to the spinal cord. Optical coherence tomography detected peripapillary retinal nerve fibre layer thickness (P<0.05) and macular ganglion cell complex volume (P<0.005) abnormalities in seven out of 10 (70.0%) patients without clinical optic neuritis. Immunosuppressants induced remission in 17 out of 22 (77.3%) patients during a median follow-up of 48 months and the median Expanded Disability Status Score was 1 (range 1–10).

Conclusion

Our study highlighted the tendency for stereotypical attacks in MOG-IgG-associated disease, heterogeneity in clinical course among subtypes, subclinical visual impairment and the need for early and sustained immunosuppressive therapy.

Genetic variations in the Dravidian population of South West coast of India: Implications in designing case-control studies

Background & objectives:

Indian data have been largely missing from genome-wide databases that provide information on genetic variations in different populations. This hinders association studies for complex disorders in India. This study was aimed to determine whether the complex genetic structure and endogamy among Indians could potentially influence the design of case-control studies for autoimmune disorders in the south Indian population.

Methods:

A total of 12 single nucleotide variations (SNVs) related to genes associated with autoimmune disorders were genotyped in 370 healthy individuals belonging to six different caste groups in southern India. Allele frequencies were estimated; genetic divergence and phylogenetic relationship within the various caste groups and other HapMap populations were ascertained.

Results:

Allele frequencies for all genotyped SNVs did not vary significantly among the different groups studied. Wright's F_ST was 0.001 per cent among study population and 0.38 per cent when compared with Gujarati in Houston (GIH) population on HapMap data. The analysis of molecular variance results showed a 97 per cent variation attributable to differences within the study population and <1 per cent variation due to differences between castes. Phylogenetic analysis showed a separation of Dravidian population from other HapMap populations and particularly from GIH population.

Interpretation & conclusions:

Despite the complex genetic origins of the Indian population, our study indicated a low level of genetic differentiation among Dravidian language-speaking people of south India. Case-control studies of association among Dravidians of south India may not require stratification based on language and caste.

Anti Myelin Oligodendrocyte Glycoprotein associated Immunoglobulin G (AntiMOG-IgG)-associated Neuromyelitis Optica Spectrum Disorder with Persistent Disease Activity and Residual Cognitive Impairment

Antibodies targeting myelin oligodendrocyte glycoprotein (MOG) have been recently reported in association with idiopathic inflammatory central nervous system disorders. Initially believed to be a benign disorder, anti MOG-IgG was noted to cause steroid responsive recurrent optic neuritis and isolated longitudinally extensive myelitis. However, there is growing evidence that the disease may be predominantly relapsing, often producing severe visual loss and involving regions other than the spinal cord and optic nerve. We report an adolescent male with an aggressive disease course previously undescribed in anti MOG-IgG-associated disease that left him with residual cognitive dysfunction.

Relapsing optic neuritis and isolated transverse myelitis are the predominant clinical phenotypes for patients with antibodies to myelin oligodendrocyte glycoprotein in India

Background

Clinical phenotypes of patients with antibodies to myelin oligodendrocyte glycoprotein (anti-MOG+) are unknown in India.

Objectives

Retrospectively to characterise anti-MOG+ patients with inflammatory central nervous system disorders in India.

Method

A total of 87 patients with non-multiple sclerosis demyelinating disorders (excluding acute disseminated encephalomyelitis) who were seronegative for anti-aquaporin 4 antibody were retrospectively analysed using a cell-based assay for anti-MOG+ status.

Results

Twenty-five patients were anti-MOG+ in this cohort. They represented 28.7% (25/87) of patients who tested negative for anti-AQP4+. Sixty-four per cent (16/25) of anti-MOG+ patients were men and had a relapsing course. Patients with recurrent optic neuritis and those with a single attack of acute longitudinally extensive transverse myelitis were the most common phenotypes.

Conclusion

Relapsing optic neuritis was the most common phenotype, contrasting with a lower risk of relapses in transverse myelitis.

European multiple sclerosis risk variants in the south Asian population

BACKGROUND

In less than a decade, genomewide association studies have identified over 100 single-nucleotide variants that are associated with increased risk of developing multiple sclerosis. However, since these studies have focused almost exclusively on European populations, it is unclear what role these variants might play in determining risk in other ethnic groups.

OBJECTIVE

To assess the effects of European multiple sclerosis-associated risk variants in the south Asian population.

METHODS

Using a combination of chip-based genotyping and next-generation sequencing, we have assessed 109 European-associated variants in a total of 270 cases and 555 controls from the south Asian population.

RESULTS

We found that two-thirds of the tested variants (72/109) showed over representation of the European risk allele in south Asian cases (p < 0.0003). In the rest of the Immunochip array, the most associated variant was rs7318477 which maps close to TNFSF13B, the gene for the B-cell-related protein BAFF.

CONCLUSION

Our data indicate substantial overlap in genetic risk architecture between Europeans and south Asians and suggest that the aetiology of the disease may be largely independent of ethnicity.

CD6 gene polymorphism rs17824933 is associated with multiple sclerosis in Indian population

Background:

Multiple sclerosis (MS) prevalence has increased worldwide. The known genetic association for MS in the west has not been studied in detail in nonwhite populations and particularly Indians.

Objective:

The objective of this study was to evaluate some known genetic variations outside the major histocompatibility complex (MHC) region associated with MS in patients of Indian origin.

Materials and Methods:

We investigated 10 gene-associated single nucleotide polymorphisms (SNP's) outside the MHC region in 300 patients and 720 unrelated controls. Genotyping was performed on an ABI7500 real-time polymerase chain reaction genotyping platform using predesigned TaqMan SNP genotyping assays.

Results:

CD6 gene associated SNP (rs17824933) showed significant association with MS (P = 4.2 × 10⁻⁵, odds ratio [OR] = 2.24, confidence interval (CI) = 1.51–3.33). A modest association was also noted for TMEM39A rs1132200 (P = 0.023, OR = 1.41, CI = 1.05–1.91) and IL2RA rs2104286 (P = 0.04, OR = 1.3, CI = 1.006–1.67). In the remaining SNPs, the allele frequencies were overexpressed in patients when compared to healthy controls.

Conclusion:

Our data illustrate the similarity in risk association between Indian and European populations for MS.

Serological markers associated with neuromyelitis optica spectrum disorders in South India

Background:

Neuromyelitis optica spectrum disorders (NMOSDs) represent 20% of all demyelinating disorders in South India. No studies have determined the seroprevalence to both antibodies against aquaporin-4* and antimyelin oligodendrocyte glycoprotein antibody (anti-MOG+) in this population.

Objective:

To identify and characterize seropositive patients for anti-aquaporin-4 antibody (anti-AQP4+) and anti-MOG+ in South India.

Materials and Methods:

We included 125 consecutive patients (15 children) who were serologically characterized using live transfected cells to human M23-AQP4 or full-length MOG.

Results:

Among a total of 125 patients, 30.4% of patients were anti-AQP4+, 20% were anti-MOG+, and 49.6% were seronegative. No patient was positive for both. Anti-MOG+ patients represented 28.7% (25/87) of seronegative NMOSD. In comparison to anti-AQP4+ patients, anti-MOG+ patients were commonly male, had less frequent attacks and milder disability on expanded disability status score scale. Seronegative patients were also predominantly male, 36% (9/25) had monophasic longitudinally extensive transverse myelitis and disability was comparable with anti-AQP4+ patients. Lumbar cord involvement was common in anti-MOG+ and seronegatives, whereas anti-AQP4+ patients had more cervical lesions.

Conclusion:

Anti-AQP4+/anti-MOG + patients accounted for nearly half of the patients suspected of having NMOSD in South India, indicating that antibody testing may be useful on the management of subgroups with different prognosis.

Neuromyelitis optica spectrum disorders: An update

Recent advances in the understanding of neuromyelitis optica spectrum of disorders (NMOSD) have expanded. Diagnostic criteria have changed over the years. The clinical spectrum of disease manifestations are now understood to include sites outside the spinal cord and optic nerve. A variety of autoimmune diseases may coexist with this disorder. Non neurological manifestations have been recently reported. Novel biomarkers other than aquoporin 4 Immunoglobulin G (anti AQP4-IgG) have been discovered which may have clinical relevance. In particul myelin associated oligoglycoprotein antibody (MOG-Ab) associated NMOSD may be relatively benign. This update describes some of these new findings highlighting the clinical manifestations, biomarkers associated with the disease and magnetic resonance imaging characteristics of brain and spinal cord.

Status of diagnostic approaches to AQP4-IgG seronegative NMO and NMO/MS overlap syndromes

Distinguishing aquaporin-4 IgG(AQP4-IgG)-negative neuromyelitis optica spectrum disorders (NMOSD) from opticospinal predominant multiple sclerosis (MS) is a clinical challenge with important treatment implications. The objective of the study was to examine whether expert clinicians diagnose and treat NMO/MS overlapping patients in a similar way. 12 AQP4-IgG-negative patients were selected to cover the range of clinical scenarios encountered in an NMO clinic. 27 NMO and MS experts reviewed their clinical vignettes, including relevant imaging and laboratory tests. Diagnoses were categorized into four groups (NMO, MS, indeterminate, other) and management into three groups (MS drugs, immunosuppression, no treatment). The mean proportion of agreement for the diagnosis was low (p o = 0.51) and ranged from 0.25 to 0.73 for individual patients. The majority opinion was divided between NMOSD versus: MS (nine cases), monophasic longitudinally extensive transverse myelitis (LETM) (1), acute disseminated encephalomyelitis (ADEM) (1) and recurrent isolated optic neuritis (RION) (1). Typical NMO features (e.g., LETM) influenced the diagnosis more than features more consistent with MS (e.g., short TM). Agreement on the treatment of patients was higher (p o = 0.64) than that on the diagnosis with immunosuppression being the most common choice not only in patients with the diagnosis of NMO (98 %) but also in those indeterminate between NMO and MS (74 %). The diagnosis in AQP4-IgG-negative NMO/MS overlap syndromes is challenging and diverse. The classification of such patients currently requires new diagnostic categories, which incorporate lesser degrees of diagnostic confidence. Long-term follow-up may identify early features or biomarkers, which can more accurately distinguish the underlying disorder.

Use of Advanced Magnetic Resonance Imaging Techniques in Neuromyelitis Optica Spectrum Disorder

Brain parenchymal lesions are frequently observed on conventional magnetic resonance imaging (MRI) scans of patients with neuromyelitis optica (NMO) spectrum disorder, but the specific morphological and temporal patterns distinguishing them unequivocally from lesions caused by other disorders have not been identified. This literature review summarizes the literature on advanced quantitative imaging measures reported for patients with NMO spectrum disorder, including proton MR spectroscopy, diffusion tensor imaging, magnetization transfer imaging, quantitative MR volumetry, and ultrahigh-field strength MRI. It was undertaken to consider the advanced MRI techniques used for patients with NMO by different specialists in the field. Although quantitative measures such as proton MR spectroscopy or magnetization transfer imaging have not reproducibly revealed diffuse brain injury, preliminary data from diffusion-weighted imaging and brain tissue volumetry indicate greater white matter than gray matter degradation. These findings could be confirmed by ultrahigh-field MRI. The use of nonconventional MRI techniques may further our understanding of the pathogenic processes in NMO spectrum disorders and may help us identify the distinct radiographic features corresponding to specific phenotypic manifestations of this disease.

Demographic and clinical features of neuromyelitis optica: A review

The comparative clinical and demographic features of neuromyelitis optica (NMO) are not well known. In this review we analyzed peer-reviewed publications for incidence and prevalence, clinical phenotypes, and demographic features of NMO. Population-based studies from Europe, South East and Southern Asia, the Caribbean, and Cuba suggest that the incidence and prevalence of NMO ranges from 0.05-0.4 and 0.52-4.4 per 100,000, respectively. Mean age at onset (32.6-45.7) and median time to first relapse (8-12 months) was similar. Most studies reported an excess of disease in women and a relapsing course, particularly in anti-aquaporin 4 antibody (anti AQP4-IgG)-positive patients. Ethnicity may have a bearing on disease phenotype and clinical outcome. Despite limitations inherent to the review process, themes noted in clinical and demographic features of NMO among different populations promote a more global understanding of NMO and strategies to address it.

HLA associations in South Asian multiple sclerosis

Background:

Previous efforts to identify Human Leukocyte Antigen (HLA) gene associations with multiple sclerosis (MS) in the South Asian population have been underpowered.

Aim:

To identify the primary HLA class II alleles associated with MS in Indians.

Methods:

We typed HLA-DRB1, -DQA1 and -DQB1 in 419 patients and 451 unrelated controls by polymerase chain reaction using sequence specific oligonucleotide probes (PCR-SSOP).

Results:

At the gene level DRB1 showed significant evidence of association ( p=0.0000012), DQA1 showed only marginal evidence of association ( p=0.04) and there was no evidence for association at DQB1 ( p=0.26). At the DRB1 locus association is confirmed with the *15:01 ( p=0.00002) and the *03 ( p=0.00005) alleles.

Conclusion:

Our study confirms that the risk effects attributable to the HLA- DRB1*15:01and DRB1*03 alleles seen in Europeans are also seen in Indians. The absence of any evidence of association with DQB1 alleles reflects the lower linkage disequilibrium between DQB1 alleles and DRB1 risk alleles present in this population, and illustrates the potential value of fine mapping signals of association in different ethnic groups.

Environmental factors related to multiple sclerosis in Indian population

BACKGROUND

Multiple sclerosis (MS) is less prevalent among Indians when compared to white populations. Genetic susceptibility remaining the same it is possible that environmental associations may have a role in determining disease prevalence.

AIMS

To determine whether childhood infections, vaccination status, past infection with Helicobacter pylori (H.pylori), diet, socioeconomic and educational status were associated with MS.

MATERIAL AND METHODS

139 patients and 278 matched control subjects were selected. A validated environmental exposure questionnaire was administered. Estimation of serum H.pylori IgG antibody was done by ELISA. Patients and controls were genotyped for HLA-DRB1*15:01.

RESULTS

In our cohort a significant association was seen with measles (p < 0.007), vegetarian diet (p < 0.001, higher educational status (p < 0.0001) and urban living (p < 0.0001). An inverse relationship was seen with H.Pylori infection and MS (p < 0.001). Measles infection (OR 6.479, CI 1.21-34.668, p < 0.029) and high educational status (OR 3.088, CI 1.212-7.872, p < 0.018) were significant risk factors associated with MS. H.pylori infection was inversely related to MS (OR 0. 319, CI 0.144- 0.706, p < 0.005).

CONCLUSIONS

Environmental influences may be important in determining MS prevalence.

Prevalence and patterns of demyelinating central nervous system disorders in urban Mangalore, South India

There is a dearth of epidemiological data about multiple sclerosis (MS) and related demyelinating disorders in India. In this study, a registry method was used for collecting data from secure sources and the index cases were verified Seventy nine patients were identified . A crude prevalence of 8.3/100,000 was obtained for MS and 6.2/100,000 for clinically-isolated syndrome (CIS). Age-standardized prevalence of MS relative to the world population was 7.8/100,000. Neuromyelitis optica (NMO) and spectrum disorders (NMOS) constituted 13.9% of all demyelinating disorders, with a prevalence of 2.6/100,000. Larger studies with more refined survey methodologies are required to understand the true prevalence of demyelinating disorders in India.

Neoplastic Parkinsonism: An illustrative case report

Non-Hodgkin's lymphoma of T-cell types are rare neoplasms. Central nervous system metastasis is unusual. We are reporting a patient with peripheral T-cell lymphoma unspecified who had extra nodal metastasis into the brain that manifested with extrapyramidal dysfunction. The clinical presentation was exceptional in that the course was indolent and patient had no overt extra neural manifestations of malignancy for nearly 3 years after the onset of Parkinsonism. Striking brain imaging late in the disease supported by pathological findings enabled the diagnosis of this rare condition.