Emerging Subspecialties in Neurology: Autoimmune neurology

Education and training in neurology: developments and future challenges

BACKGROUND AND PURPOSE

Training and education is essential for best practice medicine and is especially important in a rapidly evolving field such as neurology. Due to improved imaging techniques and laboratory testing, there is a better understanding of the pathophysiology of diseases. As a result more treatments have become available. The most important developments in neurology over the last two decades and their effect on training and education are described. In addition, how future training should be aware of the challenges ahead of us is described.

METHODS

This is a narrative review describing developments and challenges based on personal experience and the literature.

RESULTS

Due to major developments in radiological and immunological testing, major changes have been seen in different subspecialties of neurology, including but not limited to, the treatment of ischaemic stroke, the development of new entities in the field of demyelinating diseases and auto-immune encephalitis, and diffuse glioma. These developments challenge the education and training in neurology with, ahead of us, technological developments, an aging population, and potentially more superspecialization.

CONCLUSION

Although there are differences in the training curricula between European countries, the developments and future challenges within the field of neurology are very similar. In the development of future curricula it is important to face these developments and challenges and to adapt to them.

Autoimmune central nervous system disorders: Antibody testing and its clinical utility

A rapidly expanding repertoire of neural antibody biomarkers exists for autoimmune central nervous system (CNS) disorders. Following clinical recognition of an autoimmune CNS disorder, the detection of a neural antibody facilitates diagnosis and informs prognosis and management. This review considers the phenotypes, diagnostic assay methodologies, and clinical utility of neural antibodies in autoimmune CNS disorders. Autoimmune CNS disorders may present with a diverse range of clinical features. Clinical phenotype should inform the neural antibodies selected for testing via the use of phenotype-specific panels. Both serum and cerebrospinal fluid (CSF) are preferred in the vast majority of cases but for some analytes either CSF (e.g. N-methyl-D-aspartate receptor [NMDA-R] IgG) or serum (e.g. aquaporin-4 [AQP4] IgG) specimens may be preferred. Screening using 2 methods is recommended for most analytes, particularly paraneoplastic antibodies. We utilize murine tissue-based indirect immunofluorescence assay (TIFA) with subsequent confirmatory protein-specific testing. The cellular location of the target antigen informs choice of confirmatory diagnostic assay (e.g. blot for intracellular antigens such as Hu; cell-based assay for cell surface targets such as leucine-rich glioma inactivated 1 [LGI1]). Titers of positive results have limited diagnostic utility with the exception of glutamic acid decarboxylase (GAD) 65 IgG autoimmunity, which is associated with neurological disease at higher values. While novel antibodies are typically discovered using established techniques such as TIFA and immunoprecipitation-mass spectrometry, more recent high-throughput molecular technologies (such as protein microarray and phage-display immunoprecipitation sequencing) may expedite the process of antibody discovery. Individual neural antibodies inform the clinician regarding the clinical associations, oncological risk stratification and tumor histology, the likely prognosis, and immunotherapy choice. In the era of neural antibody biomarkers for autoimmune CNS disorders, access to appropriate laboratory assays for neural antibodies is of critical importance in the diagnosis and management of these disorders.

Optimizing the diagnostic performance of neural antibody testing for paraneoplastic and autoimmune encephalitis in clinical practice

The detection of neural antibodies in patients with paraneoplastic and autoimmune encephalitis has majorly advanced the diagnosis and management of neural antibody-associated diseases. Although testing for these antibodies has historically been restricted to specialized centers, assay commercialization has made this testing available to clinical chemistry laboratories worldwide. This improved test accessibility has led to reduced turnaround time and expedited diagnosis, which are beneficial to patient care. However, as the utilization of these assays has increased, so too has the need to evaluate how they perform in the clinical setting. In this chapter, we discuss assays for neural antibody detection that are in routine use, draw attention to their limitations and provide strategies to help clinicians and laboratorians overcome them, all with the aim of optimizing neural antibody testing for paraneoplastic and autoimmune encephalitis in clinical practice.

Immunosuppressors and immunomodulators in Neurology - Part I: a guide for management of patients underimmunotherapy

For patients with autoimmune diseases, the risks and benefits of immunosuppressive or immunomodulatory treatment are a matter of continual concern. Knowledge of the follow-up routine for each drug is crucial, in order to attain better outcomes and avoid new disease activity or occurrence of adverse effects. To achieve control of autoimmune diseases, immunosuppressive and immunomodulatory drugs act on different pathways of the immune response. Knowledge of the mechanisms of action of these drugs and their recommended doses, adverse reactions and risks of infection and malignancy is essential for safe treatment. Each drug has a specific safety profile, and management should be adapted for different circumstances during the treatment. Primary prophylaxis for opportunistic infections and vaccination are indispensable steps during the treatment plan, given that these prevent potential severe infectious complications. General neurologists frequently prescribe immunosuppressive and immunomodulatory drugs, and awareness of the characteristics of each drug is crucial for treatment success. Implementation of a routine before, during and after use of these drugs avoids treatment-related complications and enables superior disease control.

Autoimmune encephalitis: proposed best practice recommendations for diagnosis and acute management

The objective of this paper is to evaluate available evidence for each step in autoimmune encephalitis management and provide expert opinion when evidence is lacking. The paper approaches autoimmune encephalitis as a broad category rather than focusing on individual antibody syndromes. Core authors from the Autoimmune Encephalitis Alliance Clinicians Network reviewed literature and developed the first draft. Where evidence was lacking or controversial, an electronic survey was distributed to all members to solicit individual responses. Sixty-eight members from 17 countries answered the survey. Corticosteroids alone or combined with other agents (intravenous IG or plasmapheresis) were selected as a first-line therapy by 84% of responders for patients with a general presentation, 74% for patients presenting with faciobrachial dystonic seizures, 63% for NMDAR-IgG encephalitis and 48.5% for classical paraneoplastic encephalitis. Half the responders indicated they would add a second-line agent only if there was no response to more than one first-line agent, 32% indicated adding a second-line agent if there was no response to one first-line agent, while only 15% indicated using a second-line agent in all patients. As for the preferred second-line agent, 80% of responders chose rituximab while only 10% chose cyclophosphamide in a clinical scenario with unknown antibodies. Detailed survey results are presented in the manuscript and a summary of the diagnostic and therapeutic recommendations is presented at the conclusion.

Anti-Kir4.1 Antibodies in Multiple Sclerosis: Specificity and Pathogenicity

The glial cells in the central nervous system express diverse inward rectifying potassium channels (Kir). They express multiple Kir channel subtypes that are likely to have distinct functional roles related to their differences in conductance, and sensitivity to intracellular and extracellular factors. Dysfunction in a major astrocyte potassium channel, Kir4.1, appears as an early pathological event underlying neuronal phenotypes in several neurological diseases. The autoimmune effects on the potassium channel have not yet been fully described in the literature. However, several research groups have reported that the potassium channels are an immune target in patients with various neurological disorders. In 2012, Srivastava et al. reported about Kir4.1, a new immune target for autoantibodies in patients with multiple sclerosis (MS). Follow-up studies have been conducted by several research groups, but no clear conclusion has been reached. Most follow-up studies, including ours, have reported that the prevalence of Kir4.1-seropositive patients with MS was lower than that in the initial study. Therefore, we extensively review studies on the method of antibody testing, seroprevalence of MS, and other neurological diseases in patients with MS. Finally, based on the role of Kir4.1 in MS, we consider whether it could be an immune target in this disease.

Outcomes and future directions for neuroimmunology/multiple sclerosis fellowship training: Survey of recent trainees

BACKGROUND

Neuroimmunology/multiple sclerosis is a rapidly evolving, but still poorly defined subspecialty. Fellowship training is not standardized, and there is substantial variability across sites. Outcomes of fellowship training have not yet been studied. We therefore examined early career choices of neuroimmunology/MS fellowship program graduates and solicited the perspective of current and recent trainees on their fellowship experience as well as opportunities to improve neuroimmunology education.

METHODS

We developed a questionnaire to collect information about fellowship training experiences and current medical practice. We identified recent graduates based on records from US training programs and the National MS Society and electronically sent the survey to current trainees and recent graduates (within the last 5 years).

RESULTS

We identified 179 current/recent trainees and successfully reached 157 with survey distributions. Ninety-five individuals (60.5%) returned surveys. Most graduates assumed an academic practice (68%) focused mostly or exclusively on MS and other CNS neuroimmune diseases (55%), and practiced in regions where there were ≥5 other neuroimmunology specialists (51%). Graduates felt well-prepared to manage diagnoses of MS and neuromyelitis optica spectrum disorders but their comfort with rarer CNS neuroimmune diseases varied substantially. Basic immunology, neuro-rheumatology, grant writing and neuro-rehabilitation were identified as high impact areas for cross-disciplinary didactic training. The majority of recent trainees (57%) favored standardizing a core neuroimmunology curriculum, and 48% favored developing a subspecialty certification.

CONCLUSIONS

This is the first study to examine practice outcomes and trainee experiences for neuroimmunology training programs. We anticipate that these data will help educators define a core curriculum for the subspecialty and identify complementary skill sets that enhance the traditional clinic-based model of teaching.

Education Research: Multiple sclerosis and neuroimmunology fellowship training status in the United States

OBJECTIVE

To investigate the current status of postgraduate training in neuroimmunology and multiple sclerosis (NI/MS) in the United States.

METHODS

We developed a questionnaire to collect information on fellowship training focus, duration of training, number of fellows, funding application process, rotations, visa sponsorship, and an open-ended question about challenges facing training in NI/MS. We identified target programs and sent the questionnaires electronically to fellowship program directors.

RESULTS

We identified and sent the questionnaire to 69 NI/MS fellowship programs. We successfully obtained data from 64 programs. Most programs were small, matriculating 1-2 fellows per year, and incorporated both NI and MS training into the curriculum. Most programs were flexible in their duration, typically lasting 1-2 years, and offered opportunities for research during training. Only 56% reported the ability to sponsor nonimmigrant visas. Most institutions reported having some internal funding, although the availability of these funds varied from year to year. Several program directors identified funding availability and the current absence of national subspecialty certification as major challenges facing NI/MS training.

CONCLUSION

Our study is the first to describe the current status of NI/MS training in the United States. We found many similarities across programs. We anticipate that these data will serve as a first step towards developing a standard NI/MS curriculum and help identify areas where shared resources could enhance trainee education despite differences in training environments. We identified funding availability, certification status, and nonimmigrant visa sponsorship as potential barriers to future growth in the field.