Clinical, neuroimaging and therapeutic response in AQP4-positive NMO patients from India

Study of sleep abnormalities in patients with NMOSD-MOG related disorders

BACKGROUND

Sleep quality and architecture are rarely studied in Neuromyelitis Optica Spectrum disorder (NMOSD) and Myelin Oligodendrocyte associated disorder (MOGAD).

OBJECTIVES

To study sleep characteristics in patients with NMOSD and MOGAD.

METHODS

This prospective study (Total:72patients) was carried out in 27-Aquaporin-4positive-NMOSD (AQP4+NMO), 20-MOGAD and 25-dual seronegative NMOSD (SNNMOSD). We assessed sleep characteristics by questionnaires and nocturnal polysomnography in 10 clinically stable patients of each group and 20 healthy controls.

RESULTS

The Pittsburgh Sleep Quality Index (PSQI) (7.36±3.73,p = 0.02) and Berlin questionnaire were abnormal in SNNMOSD. Probable (RBD) (1.63±2.02,p = 0.026), anxiety (12.11±8.22,p = 0.047) and depression (9.7 ± 7.58,p = 0.009) scores were predominantly abnormal in AQP4+NMO patients. There was a positive correlation of physical disability with poor sleep quality (r = 0.29,p = 0.01), anxiety (r = 0.28,p = 0.02), depression (r = 0.24,p = 0.046) and development of RLS (r = 0.24,p = 0.04). Periodic limb movements were seen predominantly in SNNMOSD. Supratentorial lesions had higher stage-1 (N1) duration and reduced stage-2 (N2), stage-3 (N3), and REM duration. Voxel-based morphometry revealed a reduction in thalamic volume in all patients compared to healthy controls.

CONCLUSIONS

Sleep quality and architecture are impaired in NMOSD and MOGAD with significantly reduced thalamic volume. Sleep patterns reflect the extent of damage in NMOSD and MOGAD and would have implications on the comprehensive care.

Sex ratio and age of onset in AQP4 antibody-associated NMOSD: a review and meta-analysis

BACKGROUND

Aquaporin-4 (AQP4) antibody-associated neuromyelitis optica spectrum disorder (NMOSD) is an antibody-mediated inflammatory disease of the central nervous system. We have undertaken a systematic review and meta-analysis to ascertain the sex ratio and mean age of onset for AQP4 antibody associated NMOSD. We have also explored factors that impact on these demographic data.

METHODS

A systematic search of databases was conducted according to the PRISMA guidelines. Articles reporting sex distribution and age of onset for AQP4 antibody-associated NMSOD were reviewed. An initially inclusive approach involving exploration with regression meta-analysis was followed by an analysis of just AQP4 antibody positive cases.

RESULTS

A total of 528 articles were screened to yield 89 articles covering 19,415 individuals from 88 population samples. The female:male sex ratio was significantly influenced by the proportion of AQP4 antibody positive cases in the samples studied (p < 0.001). For AQP4 antibody-positive cases the overall estimate of the sex ratio was 8.89 (95% CI 7.78-10.15). For paediatric populations the estimate was 5.68 (95% CI 4.01-8.03) and for late-onset cases, it was 5.48 (95% CI 4.10-7.33). The mean age of onset was significantly associated with the mean life expectancy of the population sampled (p < 0.001). The mean age of onset for AQP4 antibody-positive cases in long-lived populations was 41.7 years versus 33.3 years in the remainder.

CONCLUSIONS

The female:male sex ratio and the mean age of onset of AQP4 antibody-associated NMOSD are significantly higher than MS. The sex ratio increases with the proportion of cases that are positive for AQP4 antibodies and the mean age of onset increases with population life expectancy.

Interest of rare autoantibodies in autoimmune encephalitis and paraneoplastic neurological syndromes: the utility (or futility) of rare antibody discovery

PURPOSE OF REVIEW

The increasing recognition and diagnosis of autoimmune encephalitis (AE) and paraneoplastic neurological syndromes (PNS) is partly due to neural autoantibody testing and discovery. The past two decades witnessed an exponential growth in the number of identified neural antibodies. This review aims to summarize recent rare antibody discoveries in the context of central nervous system (CNS) autoimmunity and evaluate the ongoing debate about their utility.

RECENT FINDINGS

In the last 5 years alone 15 novel neural autoantibody specificities were identified. These include rare neural antibody biomarkers of autoimmune encephalitis, cerebellar ataxia or other movement disorders, including multifocal presentations.

SUMMARY

Although the clinical applications of these rare antibody discoveries may be limited by the low number of positive cases, they still provide important diagnostic, prognostic, and therapeutic insights.

Double hit - A case in point for dual seropositivity to AQP4 and MOG antibodies

AQP4-IgG NMOSD (anti-aquaporin-4 neuromyelitis optica spectrum disorder) and MOGAD (myelin oligodendrocyte glycoprotein antibody associated disease) are unique disorders among themselves, with rare reports of dual seropositivity being described. Evaluation with cell-based assays reduces the incidence of false positivity. The clinical features of these cases may either have a dominant phenotype or may evolve into one subsequently. We describe a young girl aged 18-year-old who presented with longitudinally extensive transverse myelitis and dual seropositivity to both AQP4 and MOG antibodies.

Comparison of clinico-radiological profile, optical coherence tomography parameters, and outcome in MOGAD and Neuromyelitis optica spectrum disorder subtypes: A prospective observational study

Objectives

The objectives of the study were to compare the clinico-radiological profile, optical coherence tomography (OCT) parameters and outcome in Myelin Oligodendrocyte Glycoprotein-IgG-associated disorders (MOGAD) and Neuromyelitis Optica Spectrum disorder subtypes.

Materials and Methods

This prospective study involved collection of data regarding neurological assessment, neuroimaging, cerebrospinal fluid analysis, OCT parameters, treatment and outcome. Disease severity and disability were assessed using Expanded Disability Status Scale and modified Rankin scale. Patients were categorized into aquaporin-4 (AQP4+), MOGAD, and double negative (DN; both AQP4 and MOG negative).

Results

Among 31 patients included, 42% were AQP4+, 32.2% were MOGAD, and 25.7% were DN. The median age at onset was comparable (AQP4+ vs. MOGAD vs. DN = 28 years vs. 24.4 years vs. 31.5years; P = 0.31). Females predominated in AQP4+ compared to MOGAD group (76.9% vs. 30%; P = 0.02). Majority of patients (73.5%) had a relapsing course with a median of two (range = 1-9) relapses. Ninety-nine demyelinating events occurred: Transverse myelitis (TM) in 60/99 (60.6%), optic neuritis (ON) in 43/99 (43.4%), area postrema (AP) syndrome in 20/99 (20.1%), and optico-spinal syndrome in 10/99 (10.1%). ON was common in MOGAD than AQP4+ patients (58.6% vs. 32.1%; P = 0.03). Spinal cord and brain lesions on magnetic resonance imaging (MRI) were seen in 90.3% and 54.8% patients, respectively. A significantly higher proportion of AQP4+ patients showed longitudinally extensive transverse myelitis as compared to MOGAD group (69.2 % vs. 20 %; P = 0.04), specifically involving dorsal cord (92.3% vs. 50%; P = 0.02). MRI brain lesions, especially involving AP, was frequent in DN than MOGAD (47.1% vs. 6.9%; P = 0.003) and AQP4+ (47.1% vs. 18.9%; P = 0.03) patients. AQP4+ group showed significant nasal RNFL thinning on OCT (P = 0.04). Although 6-month good functional outcome was better in MOGAD than DN and AQP4+ (80% vs. 71.4% vs. 41.7%) groups, they were comparable (P = 0.13).

Conclusion

Nearly three-fourth of our patients showed a relapsing course, with TM being the most common clinical presentation. AQP4+ group showed female preponderance, frequent dorsal cord longitudinally extensive transverse myelitis, less frequent ON, and greater nasal RNFL thinning compared to MOGAD group. MRI brain lesions were more common in DN patients. All three groups exhibited good response to pulse corticosteroids and showed a comparable functional outcome at 6-month follow-up.

Seroprevalence of MOG and AQP4 Antibodies and Outcomes in an Indian Cohort of Pediatric Acquired Demyelinating Syndromes

This study aimed to determine the seropositivity of myelin oligodendrocyte glycoprotein antibodies (MOG-Ab) and aquaporin-4 antibodies (AQP4-Ab) and outcomes in children with acquired demyelinating syndromes (ADSs). Children (6 months-15 years) with suspected ADS were enrolled and tested for MOG-Ab and AQP4-Ab prospectively over 18 months at a tertiary care hospital in North India. Children with proven nonimmune-mediated neurological disorders were enrolled as controls. Of 79 children with suspected ADS, 66 were enrolled. Among the enrolled children with ADS, acute demyelinating encephalomyelitis (ADEM) (25) was the most common first clinical event followed by optic neuritis (ON) (20) and transverse myelitis (TM) (19; one child had ON and TM simultaneously [neuromyelitis optica spectrum disorders [NMOSDs]]), while two children had clinically isolated syndrome (CIS) apart from ON and TM. Fourteen (21.2%, confidence interval [CI] 11.3-31.1) tested positive for one antibody (12 [18.1%; 95% CI 10.5-25.5%] for MOG-Ab and 2 [3%; 95% CI 0-7.2%] for AQP4-Ab). None of the 62 controls tested positive for any antibody. The final diagnosis in those with the monophasic ADS was ADEM (21), ON (13), TM (16), and other CIS (1) while that in children with recurrent events was multiphasic disseminated encephalomyelitis (MDEM) (2), NMOSD (3), ADEM-ON (4), recurrent ON (4), and MS (2). Among those with the first event, 4/51 (7.8%; 95% CI 0.5-15.2%) were MOG-Ab positive and 2 AQP4-Ab positive, whereas 8/15 (53.3% [95% CI 28.1-78.6%]) with recurrent events (MDEM [2], ADEM-ON [4], recurrent ON [1], and recurrent TM [1]) were MOG-Ab positive. Hence, MOG-Abs are the most common antibodies detected in one in five children with pediatric ADS, especially in relapsing disease. AQP4-Abs are rare in children with ADS.

Prodromal emesis in MOG-antibody associated disorder

BACKGROUND

Exclusive emesis has been observed in few patients of MOG-associated disorder (MOGAD).

OBJECTIVES

To study the occurrence of emesis in patients of Demyelinating disorders and determine their clinical and radiological features.

METHODS AND RESULTS

Medical records of 551 patients of CNS demyelinating disorders were reviewed. Exclusive emesis without hiccups was observed in 1 (0.1%) patient of MS, 17 (6.5%) patients of MOGAD while none were observed in patients of AQP4-ab associated disorders (p < 0.001). There were 17(M:F-8:9) patients with exclusive emesis in MOGAD in 58.8% pediatric age group, adults (35.3%) and late-onset (5.9%). ADEMON (acute demyelinating encephalomyelitis -ADEM followed by optic neuritis) was observed in 7 patients. Preceding clinical syndrome was ON (41.2%), brainstem syndrome (BS) (23.5%), involvement of both ON and BS in 23.5%, myelopathy (11.8%). MRI analysis showed combination of lesions affecting the brainstem (11), optic nerve (10), juxtacortical white matter (10) and periventricular lesions (3). Odds ratio for the presence of ADEM, lesions in medulla, pons, MCP or any of the three areas was found to be significant.

CONCLUSIONS

Exclusive emesis without hiccups appears to be common in MOG-antibody associated disorder and may occur as a prodromal illness or exclusive clinical episode. It is known to occur most commonly in association with ADEM and/or Optic neuritis.

Clinicoradiological comparative study of Aquaporin-4-IgG seropositive neuromyelitis optica spectrum disorder (NMOSD) and MOG antibody associated disease (MOGAD): A prospective observational study and review of literature

Neuromyelitis Optica spectrum disorders (NMOSD) are autoimmune inflammatory central nervous system diseases. NMOSD patients typically have recurrent attacks of severe optic neuritis or/and myelitis with majority of them having autoantibodies against the aquaporin-4 (AQP4). In the recent past, a robust association of autoantibodies to full-length human myelin oligodendrocyte glycoprotein (MOG-IgG) with optic neuritis, myelitis and brainstem encephalitis, as well as with acute disseminated encephalomyelitis (ADEM)-like presentations had been demonstrated. MOG-IgG antibody associated disease (MOGAD) is now considered as a disease entity in its own right, distinct from classic MS and from AQP4-IgG-positive NMOSD. Here, we compared the clinical, laboratory, radiological features and treatment outcomes of patients with Aquaporin-4-IgG seropositive NMOSD and MOGAD. Relatively younger age at onset, lesser number of relapses, better response to treatment and favorable clinical outcomes were found in MOGAD group in comparison to AQP4-IgG-positive NMOSD group.

Paediatric multiple sclerosis and antibody-associated demyelination: clinical, imaging, and biological considerations for diagnosis and care

The field of acquired CNS neuroimmune demyelination in children is transforming. Progress in assay development, refinement of diagnostic criteria, increased biological insights provided by advanced neuroimaging techniques, and high-level evidence for the therapeutic efficacy of biological agents are redefining diagnosis and care. Three distinct neuroimmune conditions-multiple sclerosis, myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and aquaporin-4 antibody-associated neuromyelitis optica spectrum disorder (AQP4-NMOSD)-can now be distinguished, with evidence from humans and animal models supporting distinct pathobiological disease mechanisms. The development of highly effective therapies for adult-onset multiple sclerosis and AQP4-NMOSD that suppress relapse rate by more than 90% has motivated advocacy for trials in children. However, doing clinical trials is challenging because of the rarity of these conditions in the paediatric age group, necessitating new approaches to trial design, including age-based trajectory modelling based on phase 3 studies in adults. Despite these limitations, the future for children and adolescents living with multiple sclerosis, MOGAD, or AQP4-NMOSD is far brighter than in years past, and will be brighter still if successful therapies to promote remyelination, enhance neuroprotection, and remediate cognitive deficits can be further accelerated.

Myelin oligodendrocyte glycoprotein-antibody-associated disorder: a new inflammatory CNS demyelinating disorder

BACKGROUND AND AIMS

Myelin oligodendrocyte glycoprotein (MOG) is an oligodendrocytopathy resulting in demyelination. We aimed to determine the frequency of MOG-associated disorders (MOGAD), its various clinical phenotypes, and imaging characteristics.

METHODS

All patients with MOGAD were included. Description of the various clinical phenotypes, investigation profile, therapeutic response, differences between pediatric and adult-onset neurological disorders, determination of poor prognostic factors was done.

RESULTS

The study population consisted of 93 (M:F = 45:48) (Pediatric:40, Adult-onset:47, Late-onset:7) patients with a median age of 21 years. Among the 263 demyelinating episodes; 45.8% were optic neuritis (ON), 22.8% were myelopathy, 17.1% were brainstem, 7.6% were acute demyelinating encephalomyelitis(ADEM), 4.2% were opticomyelopathy and 2.3% with cerebral manifestations. There was exclusive vomiting in 24.7% prior to onset of clinical syndrome, none of them had area postrema involvement. ADEM was exclusively seen in pediatric patients. Poor prognostic indicators included: (i) incomplete recovery from an acute attack, (b) brainstem syndrome, (c) ADEM with incomplete recovery, (d) MRI suggestive of leukodystrophy pattern, (e) severe ON, (f) ADEMON.

CONCLUSIONS

The Spectrum of MOG-associated disorders is wider affecting the brain (grey and white matter) and the meninges. There are various clinical phenotypes and MRI patterns, recognition of which may help in the determination of therapeutic strategies, and long-term prognosis.

Therapeutic Plasma Exchange as a Treatment for Autoimmune Neurological Disease

Introduction

Therapeutic plasma exchange (TPE) is commonly used as treatment of certain autoimmune neurological diseases (ANDs), and its main objective is the removal of pathogenic autoantibodies. Our aim was to describe the clinical profile and the experience with the usage of TPE in patients with ANDs at our institution.

Methods

This is an observational retrospective study, including medical records of patients with diagnosis of ANDs who received TPE, between 2011 and 2018. Characteristics of TPE, such as number of cycles, type of replacement solution, and adverse effects, were evaluated. The modified Rankin Scale (mRS) was applied to measure the clinical response after the therapy.

Results

187 patients were included with the following diagnoses: myasthenia gravis (MG), n = 70 (37%); Guillain–Barré syndrome (GBS), n = 53 (28.3%), neuromyelitis optica spectrum disorders (NMOSD), n = 35 (18.7%); chronic inflammatory demyelinating polyneuropathy (CIDP), n = 23 (12.2%); and autoimmune encephalitis (AE), n = 6 (3.2%). The most used types of replacement solution were albumin (n = 131, 70%) and succinylated gelatin (n = 45, 24%). All patients received a median of five cycles (IQR 5-5). Hypotension and hydroelectrolytic disorders were the main complications. After TPE, 99 patients (52.9%) showed improvement in the mRS scores and a statistical significance (p < 0.05) was seen between the admission score and after TPE for every diagnosis except for CIDP.

Conclusion

TPE has an adequate safety profile, and improvement in functionality in treated patients reflects its effectiveness.

Relapse Patterns in NMOSD: Evidence for Earlier Occurrence of Optic Neuritis and Possible Seasonal Variation

Neuromyelitis optica spectrum disorders (NMOSD) and multiple sclerosis (MS) show overlap in their clinical features. We performed an analysis of relapses with the aim of determining differences between the two conditions. Cases of NMOSD and age- and sex-matched MS controls were collected from across Australia and New Zealand. Demographic and clinical information, including relapse histories, were recorded using a standard questionnaire. There were 75 cases of NMOSD and 101 MS controls. There were 328 relapses in the NMOSD cases and 375 in MS controls. Spinal cord and optic neuritis attacks were the most common relapses in both NMOSD and MS. Optic neuritis (p < 0.001) and area postrema relapses (P = 0.002) were more common in NMOSD and other brainstem attacks were more common in MS (p < 0.001). Prior to age 30 years, attacks of optic neuritis were more common in NMOSD than transverse myelitis. After 30 this pattern was reversed. Relapses in NMOSD were more likely to be treated with acute immunotherapies and were less likely to recover completely. Analysis by month of relapse in NMOSD showed a trend toward reduced risk of relapse in February to April compared to a peak in November to January (P = 0.065). Optic neuritis and transverse myelitis are the most common types of relapse in NMOSD and MS. Optic neuritis tends to occur more frequently in NMOSD prior to the age of 30, with transverse myelitis being more common thereafter. Relapses in NMOSD were more severe. A seasonal bias for relapses in spring-summer may exist in NMOSD.

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

Introduction:

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

Methods:

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

Results:

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

Conclusion:

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

Clinical and radiologic approach to 'typical' versus antibody-related optic neuritis

PURPOSE OF REVIEW

Optic neuritis is an autoimmune optic neuropathy that has been associated with multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), and more recently antimyelin oligodendrocyte glycoprotein (anti-MOG)-positive disorder. At initial presentation, it is often difficult to differentiate these entities given their significant overlap in clinical presentation and MRI findings. This review summarizes the distinguishing clinical and radiological features of MS, NMOSD, and anti-MOG disorders to help clinicians accurately diagnose and manage patients affected by these conditions.

RECENT FINDINGS

Antiaquaporin-4 (AQP4) and more recently anti-MOG antibodies are both associated with central nervous system demyelinating diseases that often initially present with optic neuritis. Serologic testing now allows for a new classification of these overlapping conditions that can help to differentiate 'typical' optic neuritis that is often associated with MS from 'atypical' optic neuritis associated with NMOSD and anti-MOG-positive disorder.

SUMMARY

Optic neuritis associated with MS, NMOSD, and anti-MOG-positive disease can have a similar clinical presentation. However, some clinical and radiologic findings can help clinicians to differentiate these entities so that they can be properly managed to optimize visual prognosis.