Frequency and Characteristics of Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease Accompanied by Fever: A Single-Center Retrospective Study.

AIMS: To evaluate the frequency and characteristics of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) accompanied by fever. METHODS: This retrospective study was conducted from April 2019 to December 2025 at Beijing Tiantan Hospital in China. Patients who met the 2023 international MOGAD panel diagnostic criteria and had a disease duration of at least 6 months were included. Febrile and afebrile groups were compared using Mann-Whitney U, χ2, and log-rank tests pre- and post-propensity score matching. Logistic regression identified factors associated with fever. RESULTS: A total of 123 patients were included. Fever occurred during 43 acute attacks in 38 (30.9%) patients, with the majority (33 attacks) representing the initial episode. The median maximal temperature was 38.6°C. Cerebral cortical encephalitis was the leading phenotype in febrile attacks (48.8%). Compared to the afebrile group, the febrile group exhibited a significantly higher median cerebrospinal fluid (CSF) leukocyte count (56/μL vs. 11.5/μL; p < 0.001) and CSF protein (52.65 mg/dL vs. 39.76 mg/dL; p = 0.001). Cerebral cortical encephalitis and CSF pleocytosis were independently associated with fever in the multivariable model. CONCLUSIONS: Fever was relatively common in our MOGAD cohort, occurring in approximately one-third of patients and across all clinical phenotypes. Both cerebral cortical encephalitis and CSF pleocytosis were independently associated with fever.