Epidemiology and clinical features of demyelinating disorders in India

The Indian multiple sclerosis and allied demyelinating disorders registry and research network (IMSRN): Inception to reality

BACKGROUND

Demyelinating disorders of the CNS are a set of chronic, inflammatory, autoimmune conditions. To improve understanding of epidemiology, population characteristics and disease behaviour, an Indian, hospital-based registry has been established to serve as a platform for fostering collaborative research. The following article outlines the development, governance and current status of the Indian Multiple Sclerosis and Allied Demyelinating Disorders Registry and Research Network (IMSRN), the country's first scientific database and dedicated expert research network of these disorders.

METHODS

Multiple reviews and stakeholder meetings were held to set up the registry. The IMSRN was formally initiated in August 2021 across 26 tertiary care centres. The registry is governed by the Indian Council of Medical Research (ICMR), New Delhi and its task force committee. The online secure database captures detailed clinical and imaging patient details at baseline and periodic follow up. Periodic meetings of the task force and collaborators are held to discuss the progress, improvements and research proposals.

RESULTS

The IMSRN is currently active and recruiting patients following an informed consent. As of current, more than 3336 patients including RIS (N = 8), CIS (N = 134), MS (N = 1674), NMOSD (N= 561), MOGAD (N = 404), ADEM (N = 46), CRION (N = 21), CLIPPERS (N = 2), and GFAP (N =1) have been enrolled. 340 patients, not meeting the diagnostic criteria for any of the aforementioned disease phenotypes are in the others category. Various research proposals are being developed to study different aspects of these disorders.

CONCLUSION

The IMSRN has been established with a vision to strengthen our understanding about MS, NMOSD, MOGAD, and other demyelinating disorders. This would help answer important questions related to disease profiles and long-term outcomes of patients in the Indian setting. From the standpoint of clinical practice, therapeutics, patient management, research, and national policy building, IMSRN shall serve as a synergising platform for bridging the gap in the aforementioned areas and guiding future research through national and international collaboration.

Clinical and radiological spectrum of acquired inflammatory demyelinating diseases of the central nervous system in a tertiary care center

Objectives

Demyelinating diseases of central nervous system (CNS) are a broad spectrum of conditions with autoimmune process against myelin. In a resource limited country like India, it is imperative to perform proper clinical evaluation, neuroimaging to differentiate among various categories of CNS demyelinating diseases to decide regarding further workup and treatment. The objective of our study was to determine clinical presentation, imaging findings, serology results, diagnosis, and treatment outcome of primary demyelinating disorders of CNS.

Materials and Methods

In this prospective study, a total of 44 patients were enrolled over a period of 1 year. After proper evaluation, patients were categorized into different groups applying newer diagnostic criteria. Patients were treated with steroids, appropriate immunomodulatory therapy, and outcomes were analyzed.

Results

The majority of cases were of neuromyelitis optica spectrum disorder (NMOSD) (45.5%) with an overall female-to-male ratio of 3.4:1 and mean age of presentation was 30.5 ± 11.15. Myelitis (52.3%) followed by optic neuritis (45.5%) was the most common initial presentation. The most common site of involvement on magnetic resonance imaging was the spinal cord (particularly the cervicodorsal cord). The majority showed good response to therapy (77.27%) and two patients did not survive.

Conclusion

Higher disability observed among seropositive NMOSD patients warrants aggressive treatment during the first attack itself. It is important to suspect myelin oligodendrocyte glycoprotein antibody disease in patients with preceding viral infection. A good outcome in the majority is likely due to the availability of serological assays and aggressive immunomodulatory therapy.

[Epidemiology of neuromyelitis optica spectrum disorder]

Neuromyelitis optica spectrum disorder (NMOSD) is a group of rare and mostly severe autoimmune demyelinating central nervous system disorders which prevalence is 0.7-1 per 100.000 population and incidence is 0.037-0.73 per 100.000 person-years. NMOSD may present as a combination of uni- or bilateral optic neuritis, transverse myelitis or lesions of brain stem and other brain regions. The symptoms are mostly relapsing (up to 97.5%) and progressive. Occurrence of relapses is associated with seropositivity for aquaporin-4 (up to 80% of NMOSD patients) and bears a less favorable prognosis (mortality up to 32%). Women seropositive for aquaporin 4 constitute 90% of NMOSD patients. Compared to other demyelinating disorders, NMOSD is characterized by late onset (mean age is about 39 years) and association with other autoimmune disorders, including systemic lupus erythematosus, myasthenia gravis and Sjogren's syndrome. A genetic predisposition was found among Blacks and Asians, with HLA-DRB1*03:01 gene associated with higher risk of NMOSD in Asians. The course of the disease tends to be more severe in Blacks. There are clusters of an increased incidence of NMOSD in the Carribeans and in the Far East. Continued increase of prevalence and incidence of NMOSD worldwide compels continued epidemiological research in order to provide early diagnosis and treatment for this disorder.