BACKGROUND: The previous Japanese clinical practice guidelines for multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) were published in 2017. Recently, for the first time in 6 years, the MS and NMOSD guideline development committee revised the Japanese guidelines for MS, NMOSD, and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD).
METHODS: The committee utilized the Grading of Recommendations Assessment, Development, and Evaluation system based on the \"Minds Handbook for Clinical Practice Guideline Development 2020 Ver. 3.0″ with a focus on clinical questions (CQs). The committee also discussed clinical issues other than CQs, categorizing them as a question-and-answer (Q&A) section, including \"issues on which experts\' opinions agree to a certain extent\" and \"issues that are important but not included in the CQ\".
RESULTS: The committee identified 3, 1, and 1 key CQs related to MS, NMOSD, and MOGAD, respectively, and presented recommendations. A Q&A session regarding disease-modifying therapies and relapse prevention therapies for MS, NMOSD, and MOGAD was conducted. The revised guidelines were published in September 2023.
CONCLUSIONS: The Japanese guidelines for clinical practice on MS, NMOSD, and MOGAD were updated. Treatment strategies for MS, NMOSD, and MOGAD are changing, and these updated guidelines may assist with treatment decisions for these diseases in clinical practice.

This article focuses on the diagnosis and management of neuromyelitis optica spectrum disorder (NMOSD). NMOSD is an autoimmune, demyelinating condition characterized by inflammation of the optic nerve and/or the spinal cord, with symptoms that can range from mild impairment of movement to paralysis. The newly approved diagnostic criteria have improved the accuracy of NMOSD diagnosis. The management of NMOSD is under major revolution due to the many new therapeutic options. The role of the antibodies directed at aquaporin-4 (AQP4) has materialized as a biomarker for NMOSD. Several new treatments that target variable aspects in immunopathology such as IL-6, complement, or depletion of B cells are emerging. The management of AQP4-negative patients remains challenging.

OBJECTIVE: Neuromyelitis optica spectrum disorder (NMOSD) is a rare demyelinating disease of the central nervous system (CNS). We investigated the medical behaviors of experts in Korea when they are diagnosing and treating NMOSD.
METHODS: An anonymous questionnaire on the diagnosis and treatment of NMOSD was distributed to experts in CNS demyelinating diseases.
RESULTS: Most respondents used the 2015 diagnostic criteria for NMOSD and applied a cerebrospinal fluid examination, magnetic resonance imaging (MRI) of the brain and spine, and anti-aquaporin-4 antibody testing to all suspected cases of NMOSD. All respondents prescribed steroid pulse therapy as an first-line therapy in the acute phase of NMOSD, and 67% prescribed azathioprine for maintenance therapy in NMOSD. However, details regarding monitoring, the tapering period of oral steroids, second-line therapy use in refractory cases, management during pregnancy, and schedule of follow-up MRI differed according to the circumstances of individual patients. We analyzed the differences in response rates between two groups of respondents according to the annual number of NMOSD patients that they treated. The group that had been treating ≥10 NMOSD patients annually preferred rituximab more often as the second-line therapy (p=0.011) and had more experience with rituximab treatment (p=0.015) compared with the group that had been treating <10 NMOSD patients.
CONCLUSIONS: This study has revealed that NMOSD experts in Korea principally follow the available treatment guidelines. However, the differences in specific clinical practices applied to uncertain cases that have been revealed will need to be investigated further in order to formulate suitable recommendations.

BACKGROUND: During the last two decades, neuromyelitis optica spectrum disorder (NMOSD) has undergone important changes, with new diagnostic markers and criteria, better recognition of clinical phenotypes, better disease prognosis and new therapeutic approaches. Consequently, management of NMOSD patients in Latin American (LATAM) has become more complex and challenging in clinical practice. In making these consensus recommendations, the aim was to review how the disease should be managed and treated among LATAM patients, in order to improve long-term outcomes in these populations.
METHODS: A panel of LATAM neurologists who are experts in demyelinating diseases and dedicated to management and care of NMOSD patients gathered virtually during 2019 and 2020 to make consensus recommendations on management and treatment of NMOSD patients in LATAM. To achieve this consensus, the RAND/UCLA methodology for reaching formal consensus was used.
RESULTS: The recommendations focused on diagnosis and differential diagnoses, disease prognosis, tailored treatment, identification of suboptimal treatment response and special circumstances management. They were based on published evidence and expert opinions.
CONCLUSIONS: The recommendations of these consensus guidelines seek to optimize management and specific treatment of NMOSD patients in LATAM.