Optimizing the management of neuromyelitis optica and spectrum disorders in resource poor settings: Experience from the Mangalore demyelinating disease registry

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).

Approach to optic neuritis: An update

Over the past few years, there has been remarkable development in the area of optic neuritis. The discovery of new antibodies has improved our understanding of the pathology of the disease. Antiaquaporin4 antibodies and antimyelin oligodendrocytes antibodies are now considered as distinct entities of optic neuritis with their specific clinical presentation, neuroimaging characteristics, treatment options, and course of the disease. Similarly, there has been a substantial change in the treatment of optic neuritis which was earlier limited to steroids and interferons. The development of new immunosuppressant drugs and monoclonal antibodies has reduced the relapses and improved the prognosis of optic neuritis as well as an associated systemic disease. This review article tends to provide an update on the approach and management of optic neuritis.

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.

Cases of neuromyelitis optica spectrum disorder from the East Africa region, highlighting challenges in diagnostics and healthcare access

Background

Neuromyelitis optica spectrum disorder (NMOSD) is an auto-immune disease of the central nervous system (CNS) associated with the IgG-antibody against aquaporin-4 (AQP4-IgG). There is little published epidemiology of NMOSD from sub-Saharan Africa (SSA).

Methods

We retrospectively collated NMOSD cases admitted to our tertiary regional neurology centre.

Results

We identified 11 cases (10 female, average age 30 years). 64% (7/11) were seropositive for AQP4-IgG, measured using indirect immunofluorescence. The remaining cases could either not afford tests, or had pathognomonic radiological features. 57% (4/7) of seropositive cases had concurrent/recent CNS infection. All patients were treated with high-dose intravenous methylprednisolone (IVMP), and 36% (4/11) also had plasma exchange. Only 55% (6/11) of the patients were seen by a neurologist at presentation: they had less relapses (1.3 vs 2.4), less diagnostic delay (2.3 vs 7.4 months), and were less disabled at the end of our review period. 10 cases were immunosuppressed long-term: 60% on mycophenolate, 30% azathioprine, and one on rituximab.

Conclusion

Our study is the largest case series of NMOSD from the East Africa region. Patients faced challenges of access to appropriate and affordable testing, and timely availability of a neurologist at onset, which had impacts on their functional outcomes. The majority of the seropositive cases had recent/concurrent CNS infections, suggesting triggered auto-immunity.

Urinary Symptoms and Bladder Dysfunction in Patients with Neuromyelitis Optica Spectrum Disorders: Evaluation with Urodynamics and Management

Objective  To assess lower urinary tract symptoms (LUTSs) in patients with neuromyelitis optica spectrum disorders (NMOSDs) and bladder dysfunction through urodynamics (filling and voiding phase of cystometrography) and management based on findings.

Patients and Methods  The study included 42 (34 females) patients admitted to the rehabilitation department. Neurologic evaluation was performed and severity of myelitis was assessed using the American Spinal Injury Association Impairment Scale. All patients underwent urodynamics, and management was based on the findings.

Results  Mean age was 34.5 years (range: 11–64 years; standard deviation: 13.1). Twenty-three (54.8%) patients had a first episode of myelitis, whereas 19 patients had relapses (number of episodes varying from 2 to 7). Eleven (26%) patients had increased frequency, 16 (37%) had urgency, 12 (28%) had urge incontinence, 8 (18.6%) had stress incontinence, 22 (52.4%) had nocturia, 31 (72%) had retention of urine, 22 (52.4%) had incomplete evacuation, and 14 (33.3%) patients had mixed urinary complaints. The common urodynamic findings were neurogenic detrusor overactivity (NDO) with detrusor-sphincter dyssynergia (DSD) in 14 (33.3%) patients, NDO without DSD in 8 (19%), and acontractile detrusor in 20 (47.6%). Pharmacotherapy was advised to 22 (52.4%) patients, whereas clean intermittent catheterization (CIC)/self-catheterization was advised to 39 (92.9%) patients.

Conclusions  Urinary retention was observed to be the most common urinary complaint in patients with NMOSD followed by NDO with or without sphincter dyssynergia. Urodynamics should be performed in all patients with LUTSs for best management. CIC remains the gold standard for the management of neurogenic bladder dysfunction.

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.

Admission diagnoses of patients later diagnosed with autoimmune encephalitis

BACKGROUND

Since the detection of autoantibodies against neuronal surface antigens, autoimmune encephalitis (AE) has been more frequently diagnosed, especially in patients with symptoms typical of limbic encephalitis, such as seizures, short-term memory deficits, or psychosis. However, the clinical spectrum of AE may be much wider, making correct clinical diagnosis difficult.

METHODS

We retrospectively analysed symptoms and admission diagnoses at first clinical presentation in 50 AE patients. We included patients with a clinical diagnosis of AE for whom a FDG-PET imaging was available. Final diagnoses were re-evaluated by a blinded investigator according to the most recent consensus suggestions published in 2016 for AE diagnostic criteria. We additionally describe two patients with Morvan syndrome who showed CASPR2 antibodies.

RESULTS

In 40 patients (80.0%), the clinical presentation at first admission was typical for AE. Ten patients (20.0%) initially suffered from atypical symptoms; among these patients, isolated headache and cerebellar dysfunction were most frequent (three patients each). However, an initial diagnosis of suspected encephalitis was only reached in 16 patients (32.0%), nine (18.0) of which were suspected to have infectious encephalitis, and seven (14.0%) patients were suspected to have AE. In 34 patients (68.0%), a diagnosis other than encephalitis was considered, (e.g., epilepsy, psychiatric diseases, transient ischemic attack, dementia, meningitis, and cerebellitis).

CONCLUSIONS

These data show the broad spectrum of initial symptoms of AE; the correct initial diagnosis of AE is often missed or delayed. Hence, clinicians in neurological and psychiatric hospitals should consider AE in the differential diagnosis of cases with atypical clinical presentations.

Prevalence of anti-aquaporin 4 antibody in a diagnostic cohort of patients being investigated for possible neuromyelitis optica spectrum disorder in Western Australia

OBJECTIVE

To evaluate the prevalence of anti-AQP4 antibody in serum and CSF samples from patients being investigated for possible neuromyelitis optica spectrum disorder (NMOSD) referred to the PathWest State reference laboratory using a sensitive cell-based assay (CBA).

BACKGROUND

NMOSD is an inflammatory CNS disease distinct from MS, which is relatively rare in Western countries. A proportion of patients with NMOSD have detectable serum IgG antibodies that target the water channel aquaporin-4 (AQP4-IgG), but the frequency varies in different populations studied and according to the assay method employed.

METHODS

Sera or CSF from a diagnostic cohort of 196 consecutive patients with possible NMOSD which had previously been screened by indirect immunofluorescence (IIF) on primate cerebellum were re-tested for AQP4-IgG reactivity to the M1 and M23 isoforms of AQP4 using a commercial CBA. A control group of 205 patients with definite MS was also included in the study.

RESULTS

Of the 196 patients, only 5 sera were AQP4-IgG positive, representing 2.6% of patients in the diagnostic cohort. All 5 AQP4-IgG positive patients fulfilled the 2015 revised diagnostic criteria for NMOSD and were females of varied ethnic origins, 4 of whom had longitudinally extensive transverse myelitis. The CBA confirmed AQP4-IgG positivity in the four patients previously reported as positive by IIF, and an additional patient with NMOSD who had previously been diagnosed as MS was also identified. None of the 205 MS sera were AQP4-IgG positive.

CONCLUSIONS

Our study confirms the utility and greater reliability of the M1/M23 CBA for detecting AQP4-IgG in patients with possible NMOSD, and indicates a prevalence of seropositive NMOSD in the Western Australian population similar to that in other Western populations.

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.

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.

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.