[Toxoplasmosis in the practice of a neurologist]. / Toksoplazmoz v praktike nevrologa.

Toxoplasmosis is a zoonotic protozoal disease characterized by a chronic course, polymorphism of clinical manifestations, predominant damage to the central nervous system, organs of vision, liver and lungs. The causative agent of the disease is the obligate intracellular parasite Toxoplasma gondii, which circulates widely in the external environment and has a large circle of intermediate hosts. Toxoplasmosis is classified by the method of infection (congenital or acquired), by pathogenesis (acute or chronic), by manifestation (latent or with the manifestation of symptoms). According to the state of the human immune system, the disease can occur without immunodeficiency, while the patient has a chronic lifelong carrier, and with immunodeficiency. People with HIV most commonly present with cerebral toxoplasmosis. The article presents a case of the development of toxoplasmosis in a patient in the absence of a burdened history.

Training of neurologists for the 21st century: cultural and professional skills.

Training of neurologists for the near future is a challenge due to the likely advances in neuroscientific methods, which will change much of our knowledge on diagnosis and treatment of neurological diseases. OBJECTIVE: to comment on what may be more likely to be a constant in the very near future and to recommend how to prepare the neurologist for the 21st century. METHODS: through a critical review of recent articles on the teaching of Neurology, to present a personal view on the subject. RESULTS: Diagnostic methods and therapeutic resources in Neurology will be greatly improved, but the central core of teaching young neurologists will continue to be the clinical/anatomical correlation. The neurologist must be prepared to be the primary physician in the care of patients with neurological disorders, although the roles of consultant and clinical neuroscientist must also be considered. In addition to technical knowledge, the neurologist must be prepared to discuss not only distressing issues related to the specialty, such as the risks of genetic diseases for family members of their patients, the inexorable progression of some diseases and the need for palliative care, but also problems not directly related to Neurology that cause anxiety and depression in the patient or that are the main reason for the initial consultation. CONCLUSION: neurology will be an even more important area of medicine and the neurologist must be well prepared to be the primary doctor to diagnose, treat and follow the patient with neurological disorders. In addition to technical knowledge, training in doctor-patient relations should be highlighted.

[Telecare in Parkinson's disease: A nationwide survey among Hungarian neurologists]. / Távellátás Parkinson-kórban: országos felmérés a magyar neurológusok körében.

Background and purpose: COVID-19 has made providing in-person care difficult. In most countries, including Hungary, telemedicine has partly served as a resolution for this issue. Our purpose was to explore the effects of COVID-19 on neurological care, the knowledge of neurology specialists on telemedicine, and the present state of telecare in Hungary, with a special focus on Parkinson's disease (PD). Methods: Between July and October 2021, a nationwide online survey was conducted among actively practicing Hungarian neurology specialists who were managing patients with PD. Results: A total of 104 neurologists were surveyed. All levels of care were evaluated in both publicly funded and private healthcare. Both time weekly spent on outpatient specialty consultation and the number of patients with PD seen weekly significantly decreased in public healthcare, while remained almost unchanged in private care (p<0.001); higher portion of patients were able to receive in-person care in private care (78.8% vs. 90.8%, p<0.001). In telecare, prescribing medicines has already been performed by the most (n=103, 99%). Electronic messages were the most widely known telemedicine tools (n=98, 94.2%), while phone call has already been used by most neurologists (n=95, 91.3%). Video-based consultation has been more widely used in private than public care (30.1% vs. 15.5%, p=0.001). Teleprocedures were considered most suitable for monitoring progression and symptoms of Parkinson's disease and evaluating the need for adjustments to antiparkinsonian pharmacotherapy. Conclusion: COVID-19 has had a major impact on the care of patients with PD in Hungary. Telemedicine has mitigated these detrimental effects; however, further developments could make it an even more reliable component of care.

Do the neurologists recognize autoimmune epilepsy well enough? What is the effect of the pandemic on this matter?

INTRODUCTION: The concept of "autoimmune epilepsy" (AE) has been emphasized more frequently through the recent increase in recognition of various autoantibodies specific to neuronal proteins. AIMS: To evaluate the attitudes of neurologists in regard to AE, to review the differential diagnosis, treatment options, and to reveal the effect of COVID-19 on this matter. METHODS: A detailed questionnaire prepared for AE was sent to neurologists via social media and WhatsApp after the approval of the Ethics Committee. The responses of 245 respondents working in different settings were analyzed, and the group with 15 years or less experience in neurology was statistically compared to the group with more than 15 years of experience. RESULTS: Awareness and knowledge levels on AE seemed high in all groups, while 11% had never thought about AE during the differential diagnosis in real life. Before starting treatment, 20% thought that the autoantibody result should definitely support it, and 77.6% reported that they did not recognize AE well. Participants stated that satisfactory guidelines for diagnosis and treatment (88.2%) and widespread laboratory support (83.7%) were lacking. Neurologists with less experience and those working outside of training hospitals get more often consultation from an experienced clinician while diagnosing and conduct more detailed investigations at the diagnosis stage (p = 0.0025, p = 0.0001). CONCLUSION: This first survey study conducted in a large group of neurologists on the attitudes for the concept of AE suggested that postgraduate education, and diagnostic and treatment guidelines should be organized and antibody screening tests need to be better disseminated.

Watch out for neuromyelitis optica spectrum disorder onset or clinical relapse after COVID-19 vaccination: What neurologists need to know?

INTRODUCTION: The ongoing global COVID-19 pandemic has dramatically impacted our lives. We conducted this systematic review to investigate the safety of the COVID-19 vaccines in NMOSD patients. METHODS: We systematically searched PubMed, Scopus, Web of Science, and Embase from the beginning of the COVID-19 vaccination to March 1, 2022. Except for the letters, posters, and reviews, we included all related articles to answer two main questions. Our first question examined the occurrence of NMOSD onset as an adverse effect of the COVID-19 vaccine. Our second question investigated the safety of the COVID-19 vaccines in NMOSD patients. RESULTS: Out of 262 records, nine studies, including five studies for the first question and four studies for the second question, met the inclusion criteria. Out of the six patients with NMOSD onset after COVID-19 vaccination, five (83.3%) were female. The median time to NMOSD onset was 6.5 days, and the frequency of the COVID-19 vaccine type was identical in all patients. The most common presentation was longitudinally extensive transverse myelitis, significantly improved by pulse methylprednisolone with or without plasma exchange. The maintenance therapy was described only in three patients: rituximab (n=2) and azathioprine (n=1). Regarding the second question, out of 67 patients, 77.61% were female, with a mean age of 54.75 years old, a mean EDSS of 2.83, and a mean disease duration of 9.5 years. 77% reported at least one preexisting comorbidity. 88.05% were under treatment, most of which were rituximab and azathioprine. 98.50% received two doses of the COVID-19 vaccine. mRNA vaccines were the most commonly used vaccine(86.56%), which were well tolerated. No significant adverse event was reported, and local pain was the most frequently reported. 4.67% of the patients experienced a clinical relapse after a mean interval of 49.75 days, which was mainly mild to moderate in severity. Unfortunately, the data on the COVID-19 vaccines were missing. CONCLUSION: The analysis suggests the safety profile of the COVID-19 vaccines. All NMOSD patients are strongly recommended to vaccinate for COVID-19. To maximize the effectiveness of the COVID-19 vaccines, further studies are needed to draw the best practice for vaccination.

Medicolegal Priorities for a Neurosurgeon/Neurologist in the COVID Era.

Vulnerable moments, panic, and uncertainties are the hallmarks of pandemic outbreaks. Medicolegal challenges add further injury to the public health chaos. Although containing the pandemic is of prime concern, medicolegal and ethical uncertainties further complicate ideal standards of medical care. Constraints in the provision of medical care, resource limitations, infectivity risks, burgeoning costs, and pandemic control laws, create extremely precarious medicolegal situations. Ethics and medical negligence laws may, at times, be trampled upon by the overwhelming urgencies of the pandemic. Hence, we attempt to review basic ethical and medicolegal principles that are put to test by pandemic urgencies. We aim to study these vulnerable medicolegal moments in neurosurgeons'/neurologists' clinical and research practices during the COVID-19 times from our own practice and contemporary literature on COVID practices, medicolegal sciences, and pandemic healthcare directives. We also review supportive measures and safeguards to brace these vulnerable moments effectively. We compile medicolegally sound and ideal practice parameters, including the basic principles for a restructured informed surgical consent ensuring a medicolegally and ethically sound practice. Several ethical and medicolegal exigencies are part of medical practice during a pandemic. Special care should be taken to avoid violations of medicolegal and ethical proprieties during the urgencies of medical care and research. Restructuring of contracts like the informed consent would also count as an ideal practice modification in a pandemic.

Diagnosis and Management of Suspected Pediatric Autoimmune Encephalitis: A Comprehensive, Multidisciplinary Approach and Review of Literature.

Autoimmune encephalitis is an increasingly recognized entity in children. When treated promptly, favorable outcomes are seen in a majority of pediatric patients. However, recognition of autoimmune encephalitis in young patients is challenging. Once autoimmune encephalitis is suspected, additional difficulties exist regarding timing of treatment initiation and duration of treatment, as evidence to guide management of these patients is emerging. Here, we review available literature regarding pediatric autoimmune encephalitis and present our institution's comprehensive approach to the evaluation and management of the disease. These guidelines were developed through an iterative process involving both pediatric neurologists and rheumatologists.

How did the COVID-19 Pandemic Affect Pediatric Neurologists?

BACKGROUND: In addition to physical health, pandemics affect mental health. The aim was to reveal problems encountered during the coronavirus disease 2019 (COVID-19) pandemic by pediatric neurologists and pediatric neurology residents in Turkey. METHODS: Participants were sent a survey form using Google Forms between November 05, 2020, and December 07, 2020. The form included questions about demographic information, changes to services offered, effects of the COVID-19 pandemic on patient follow-up/treatment and doctor decision-making, the Depression-Anxiety-Stress Scale 21, and the Impact of Events scale for posttraumatic stress disorder. RESULTS: A total of 232 pediatric neurologists and residents (mean age: 40.67 ± 7.8 years) participated. Of these 182 participants (78.4%) stated the pandemic had affected decisions during diagnosis and treatment management. A total of 222 participants completed the Depression-Anxiety-Stress Scale 21 and Impact of Events scale. Of these, points at levels that were "severe and very severe" were present for 42 participants (18.9%) for depression, 29 participants for anxiety (13%), and 31 participants for stress (14%). Impact of Events scale points were high at "severe" levels for 122 participants (55%). All scores were higher for those with individuals at risk in terms of COVID-19 in their family compared with those without individuals at risk in the family (P < 0.05). CONCLUSIONS: As we emerge from the destruction caused by COVID-19, it will be beneficial not only for our professional practice but also in terms of our individual health to learn lessons that will assist in managing the next pandemic waiting in our future.

COVID-19 and neurologic manifestations: a synthesis from the child neurologist's corner.

BACKGROUND: Since December 2019, the SARS-CoV-2 virus has been a global health issue. The main clinical presentation of this virus is a flu-like disease; however, patients with diverse neurologic manifestations have also been reported. In this review, we attempt to summarize, discuss and update the knowledge of the neurologic manifestations in the pediatric population affected by SARS-CoV-2 infection and the pandemic's effects in children with neurologic diseases. DATA SOURCES: This review analyzes studies found on the PubMed database using the following keywords: Neurologic manifestations COVID-19, Neurological COVID-19, coronavirus, SARS-CoV-2, pediatric COVID-19, COVID-19 in children, MIS-C, Pediatric Inflammatory Multisystem Syndrome, Guillain Barré Syndrome, Stroke, ADEM, and Anti-NMDA encephalitis. All studies cited were published between 2004 and 2022, and represent the most relevant articles in the field. The World Health Organization COVID-19 online dashboard was assessed to obtain updated epidemiological data. RESULTS: The most common neurologic symptoms in the pediatric population are headache, seizures, encephalopathy, and muscle weakness. These can be present during COVID-19 or weeks after recovering from it. Children who presented with multi-system inflammatory syndrome had a higher incidence of neurologic manifestations, which conferred a greater risk of morbidity and mortality. Several neuro-pathophysiological mechanisms have been proposed, including direct virus invasion, hyper-inflammatory reactions, multi-systemic failure, prothrombotic states, and immune-mediated processes. On the other hand, the COVID-19 pandemic has affected patients with neurologic diseases, making it challenging to access controls, treatment, and therapies. CONCLUSIONS: Various neurologic manifestations have been associated with children's SARS-CoV-2 infection. It is important to identify and give them proper and opportune treatment because they can be potentially grave and life-threatening; some can lead to long-lasting sequelae. Different neuro-pathophysiological mechanisms have been proposed, however, a causal relationship between SARS-CoV-2 infection and neurologic manifestations remains to be proven. Patients with neurologic diseases are especially affected by COVID-19, not only by the disease itself but also by its complications and pandemic management measures.

Neurologists' Knowledge, Practice, and Attitudes towards Pharmacovigilance and Adverse Drug Reactions Reporting Process in Epileptic Patients-Comparative Analysis from Poland and Egypt.

OBJECTIVES: To compare neurologists' knowledge, practice, and barriers of pharmacovigilance (PV) process among patients with epilepsy in Poland and Egypt. METHODS: It was an international study that used an online questionnaire e-mailed to neurologists registered to practice in Poland and Egypt. RESULTS: Most of the neurologists were familiar with the definition of PV and adverse drug reactions (ADRs), but relatively few neurologists knew where to report ADRs, especially the Egyptian neurologists. Only 31.11% of the neurologists from Egypt and 39.90% neurologists from Poland declared that they had reported ADRs at least once during their professional practice, and few of them declared the regular reporting of such incidents. The main reason for the neurologists not reporting ADRs was the lack of time and a conviction that reporting ADRs would be an additional burden that would generate extra work. CONCLUSION: The standards of pharmacovigilance process, safety control, and quality are not the same throughout the world. System-regulated PV stabilization in a country translates into the practice of maintaining PV. Monitoring the safety of pharmacotherapy and knowledge of risks associated with ADRs should be included in the academic curricula of physician courses.

Implementation of a Teleneurology Clinic in Zambia during the COVID-19 Pandemic.

OBJECTIVE: The objective of this study was to assess the feasibility, acceptability, and benefits of a teleneurology clinic serving adults usually attending a neurology outpatient clinic in Lusaka, Zambia during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: Televisits were offered to patients scheduled for neurology appointments between March and July 2020 using the telephone, WhatsApp video, or Zoom calls based on patient accessibility. Visit outcomes were documented, and patient and neurologist satisfaction surveys were completed. RESULTS: Of 323 patients, 195 (60%) were reachable by telephone, 179 of these were alive, and 74% (133/179) of those alive agreed to a televisit. Stroke (30%), seizures (20%), and headache (16%) were the most common diagnoses seen via televisit. Most televisits (80%) were by telephone call, 14% by WhatsApp video call, and 6% by Zoom. Nearly one-third (30%) of the patients were stable and discharged from the clinic, 32% only required medication refills, and 19% required an in-person visit. Sixty patients (out of 85 reachable and 71% response rate) and 7 of 9 neurologists (78% response rate) completed satisfaction surveys. Neurologists reported greater assessment confidence with Zoom, but confidence was high for all modalities. Patients preferring televisits (75%, 45/60) noted reduced expense and time requirements, whereas those preferring in-person visits (22%, 13/60) cited the desire for physical examinations. Overall, 98% of patients and 100% of neurologists were satisfied with televisits. INTERPRETATION: Teleneurology visits were acceptable and feasible for adults attending an outpatient neurology clinic in Zambia and their neurologists. They offer a promising supplement to in-person visits in resource-limited settings, even when video-conference capabilities and electronic medical records are absent. ANN NEUROL 2022;91:445-454.

Did the role of the neurologist in the emergency department change during the COVID-19 pandemic? Evidence from an Italian nationwide survey.

OBJECTIVE: This study aims to assess whether the role of neurologists in the emergency department changed during the coronavirus (COVID)-19 pandemic. METHODS: Data from an Italian national survey investigating the role of neurologists in the emergency room conducted in December 2020 were compared with those of the same survey of the previous year. These surveys involved a questionnaire being completed filled in for patients who received a neurological consultation following a visit to the emergency room. Information gathered included demographic characteristics, triage level according to both the emergency physician and neurologist, reason for the consultation, neurological evaluation, and discharge mode. RESULTS: In both years, approximately half of the patients were women, and the median age was 61 years. More patients in 2020 arrived by ambulance and had a greater need for assistance based on triage level than in 2019. During 2020, the proportion of consultancy requests judged by the neurologist was higher than that in 2019 (77% vs. 73%). Moreover, in 2020, fewer patients required consultation for headache, muscle pain, fever, and neurological signs, whereas coma was more prevalent. The diagnosis of ischemic stroke was the most prevalent in both years, followed by transient ischemic attack. In 2020, the status epilepticus increased and discopathy decreased. CONCLUSION: This study showed the significant role played by neurologists in emergency activities, especially during the COVID-19 pandemic, and highlighted the differences in patients admitted between the year of the epidemic and the year previous.

Masking for School-Age Children With Epilepsy: We Do Have Consensus!

INTRODUCTION: This study was designed to assess current recommendations from child neurologists and epileptologists on masking for school-age children with epilepsy. METHODS: A 7-item survey was created and sent out to members of the Child Neurology Society and Pediatric Epilepsy Research Consortium in August of 2021 to assess current practice and provider recommendations on masking. RESULTS: One hundred four individuals participated with representation from all regions of the United States. Masking was recommended by 95.1%, with 63.4% (n = 66) noting exception of those with severe intellectual disability, autism, and behavioral problems. Of those who write exemption letters, 54% write these <5% of the time. Only 3% reported potential adverse events associated with masking. CONCLUSION: Nearly all respondents recommended masking for school-age children with epilepsy. Potential risks of masking and adverse events were low. Improved guidance on masking is needed to ensure academic success of our patients with epilepsy.

Sodium and water perturbations in patients who had an acute stroke: clinical relevance and management strategies for the neurologist.

Sodium and water perturbations, manifesting as hyponatraemia and hypernatraemia, are common in patients who had an acute stroke, and are associated with worse outcomes and increased mortality. Other non-stroke-related causes of sodium and water perturbations in these patients include underlying comorbidities and concomitant medications. Additionally, hospitalised patients who had an acute stroke may receive excessive intravenous hypotonic solutions, have poor fluid intake due to impaired neurocognition and consciousness, may develop sepsis or are administered drugs (eg, mannitol); factors that can further alter serum sodium levels. Sodium and water perturbations can also be exacerbated by the development of endocrine consequences after an acute stroke, including secondary adrenal insufficiency, syndrome of inappropriate antidiuretic hormone secretion and diabetes insipidus. Recently, COVID-19 infection has been reported to increase the risk of development of sodium and water perturbations that may further worsen the outcomes of patients who had an acute stroke. Because there are currently no accepted consensus guidelines on the management of sodium and water perturbations in patients who had an acute stroke, we conducted a systematic review of the literature published in English and in peer-reviewed journals between January 2000 and December 2020, according to PRISMA guidelines, to assess on the current knowledge and clinical practices of this condition. In this review, we discuss the signs and symptoms of hyponatraemia and hypernatraemia, the pathogenesis of hyponatraemia and hypernatraemia, their clinical relevance, and we provide our recommendations for effective treatment strategies for the neurologist in the management of sodium and water perturbations in commonly encountered aetiologies of patients who had an acute stroke.

Impact of Covid-19 on the therapeutic plasma exchange service within the South East Asian region: Consensus recommendations and global perspectives.

INTRODUCTION: Therapeutic plasma exchange (TPE) for neuroimmunological disorders has played an increasingly important role within the Southeast Asian (SEA) region. The South East Asian Therapeutic Plasma exchange Consortium (SEATPEC) was formed in 2018 to promote education and research on TPE within the region. The advent of the Covid-19 pandemic has produced challenges for the development and expansion of this service. METHODOLOGY: A qualitative and semi-quantitative questionnaire-based survey was conducted by SEATPEC member countries from January to June 2020 (Phase 1) and then from July 2020 to January 2021 in (Phase 2) to assess the impact of Covid-19 on regional TPE. OBJECTIVES: The study's main objectives were to explore the challenges experienced and adaptations/adjustments taken by SEATPEC countries in order to continue safe and efficient TPE during the Covid-19 pandemic. RESULTS: The pandemic was found to disrupt the delivery of TPE services in all SEATPEC countries. Contributing factors were multifactorial due to overstretched medical services, staff shortages, quarantines and redeployments, fear of acquiring Covid-19, movement restriction orders, and patient's psychological fear of attending hospitals/testing for Covid-19. All SEATPEC countries practiced careful stratification of cases for TPE (electives vs emergencies, Covid-19 vs non-Covid-19 cases). SEATPEC countries had to modify TPE treatment protocols to include careful preprocedure screening of patient's for Covid-19, use of personal protective equipment (PPE) and post-TPE sanitization of machines and TPE suites. CONCLUSION: Based on the responses of the survey, SEATPEC countries produced a consensus statement with five recommendations for safe and effective TPE within the region.

North American survey on impact of the COVID-19 pandemic shutdown on DBS care.

BACKGROUND: The initial COVID-19 pandemic shutdown led to the canceling of elective surgeries throughout most of the USA and Canada. OBJECTIVE: This survey was carried out on behalf of the Parkinson Study Group (PSG) to understand the impact of the shutdown on deep brain stimulation (DBS) practices in North America. METHODS: A survey was distributed through RedCap® to the members of the PSG Functional Neurosurgical Working Group. Only one member from each site was asked to respond to the survey. Responses were collected from May 15 to June 6, 2020. RESULTS: Twenty-three sites participated; 19 (83%) sites were from the USA and 4 (17%) from Canada. Twenty-one sites were academic medical centers. COVID-19 associated DBS restrictions were in place from 4 to 16 weeks. One-third of sites halted preoperative evaluations, while two-thirds of the sites offered limited preoperative evaluations. Institutional policy was the main contributor for the reported practice changes, with 87% of the sites additionally reporting patient-driven surgical delays secondary to pandemic concerns. Pre-post DBS associated management changes affected preoperative assessments 96%; electrode placement 87%; new implantable pulse generator (IPG) placement 83%; IPG replacement 65%; immediate postoperative DBS programming 74%; and routine DBS programming 91%. CONCLUSION: The COVID-19 pandemic related shutdown resulted in DBS practice changes in almost all North American sites who responded to this large survey. Information learned could inform development of future contingency plans to reduce patient delays in care under similar circumstances.

Experience of Community Neurologists Providing Care for Patients With Neurodegenerative Illness During the COVID-19 Pandemic.

OBJECTIVE: Health care delivery systems transformed rapidly at the beginning of the coronavirus disease 2019 (COVID-19) pandemic to slow the spread of the virus while identifying novel methods for providing care. In many ways, the pandemic affected both persons with neurologic illness and neurologists. This study describes the perspectives and experiences of community neurologists providing care for patients with neurodegenerative illnesses during the COVID-19 pandemic. METHODS: We conducted a qualitative study with 20 community neurologists from a multisite comparative-effectiveness trial of outpatient palliative care from July 23, 2020, to November 11, 2020. Participants were interviewed individually about the impact of the coronavirus disease 2019 (COVID-19) pandemic on their professional and personal lives. Interviews were analyzed with matrix analysis to identify key themes. RESULTS: Four main themes illustrated the impact of the pandemic on community neurologists: (1) challenges of the current political climate, (2) lack of support for new models of care, (3) being on the frontline of suffering, and (4) clinician self-care. Taken together, the themes capture the unusual environment in which community neurologists practice, the lack of clinician trust among some patients, patient and professional isolation, and opportunities to support quality care delivery. CONCLUSIONS: The COVID-19 pandemic and pandemic politics created an environment that made care provision challenging for community neurologists. Efforts to improve care delivery should proactively work to reduce clinician burnout while incorporating support for new models of care adopted due to the pandemic. TRIAL REGISTRATION INFORMATION: ClinicalTrials.gov identifier: NCT03076671.

Consensus disease definitions for neurologic immune-related adverse events of immune checkpoint inhibitors.

Expanding the US Food and Drug Administration-approved indications for immune checkpoint inhibitors in patients with cancer has resulted in therapeutic success and immune-related adverse events (irAEs). Neurologic irAEs (irAE-Ns) have an incidence of 1%-12% and a high fatality rate relative to other irAEs. Lack of standardized disease definitions and accurate phenotyping leads to syndrome misclassification and impedes development of evidence-based treatments and translational research. The objective of this study was to develop consensus guidance for an approach to irAE-Ns including disease definitions and severity grading. A working group of four neurologists drafted irAE-N consensus guidance and definitions, which were reviewed by the multidisciplinary Neuro irAE Disease Definition Panel including oncologists and irAE experts. A modified Delphi consensus process was used, with two rounds of anonymous ratings by panelists and two meetings to discuss areas of controversy. Panelists rated content for usability, appropriateness and accuracy on 9-point scales in electronic surveys and provided free text comments. Aggregated survey responses were incorporated into revised definitions. Consensus was based on numeric ratings using the RAND/University of California Los Angeles (UCLA) Appropriateness Method with prespecified definitions. 27 panelists from 15 academic medical centers voted on a total of 53 rating scales (6 general guidance, 24 central and 18 peripheral nervous system disease definition components, 3 severity criteria and 2 clinical trial adjudication statements); of these, 77% (41/53) received first round consensus. After revisions, all items received second round consensus. Consensus definitions were achieved for seven core disorders: irMeningitis, irEncephalitis, irDemyelinating disease, irVasculitis, irNeuropathy, irNeuromuscular junction disorders and irMyopathy. For each disorder, six descriptors of diagnostic components are used: disease subtype, diagnostic certainty, severity, autoantibody association, exacerbation of pre-existing disease or de novo presentation, and presence or absence of concurrent irAE(s). These disease definitions standardize irAE-N classification. Diagnostic certainty is not always directly linked to certainty to treat as an irAE-N (ie, one might treat events in the probable or possible category). Given consensus on accuracy and usability from a representative panel group, we anticipate that the definitions will be used broadly across clinical and research settings.