[Clinical follow-up study of myelin oligodendrocyte glycoprotein antibody-associated disease in children].

Objective: To summarize the clinical characteristics of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and compare the differences in efficacy of different disease-modifying drugs. Methods: An ambispective cohort study was conducted in 42 children diagnosed with MOGAD at Department of Pediatrics, Peking University First Hospital from January 2012 to March 2021 and conducted long-term follow-up to analyze clinical phenotypes and compare the efficacy of different disease-modifying drugs such as rituximab, mycophenolate mofetil and azathioprine. Kruskal-Wallis H test was used to compare the annual relapse rate of disease-modifying drugs at different times, expanded disability status scale (EDSS) score at the last follow-up, and Wilcoxon rank test was used to compare the annual relapse rate before and after modified disease therapy. The Log-rank (Mantel-Cox) survival curve was used to compare the relapse rate of different disease-modifying drugs. Results: Of the 42 cases, 22 were male and 20 were female, with the age at disease onset of 5.96 (2.33-12.90) years. The disease duration was 4.46 (1.25-13.00) years at the last follow-up with 161 clinical acute attacks. Acute disseminated encephalomyelitis (ADEM) was the most common phenotype of first attack and all attacks during disease course ((60% (25/42) for first attack, 38% (61/161) for all attacks). The most common clinical syndrome was neuromyelitis optica spectrum disorders (NMOSD) (50%, 21/42). Of the 42 children, 5 (12%) showed encephalitis and 6 (14%) combined with anti-N-methyl-D-aspartate receptor (NMDAR) antibody overlap syndrome. The most commonly involved areas of brain magnetic resonance imaging (MRI) were subcortical white matter (71%, 88/124), cortex (26%, 32/124) and periventricular white matter (25%, 32/124). Spinal cord MRI was most frequently involved in cervical (70%, 16/23) and thoracic (61%, 14/23) medulla, and 43% (10/23) longitudinally extensive transeverse myelitis. Disease-modifying drugs were used in 34 patients. The annual relapse rate after treatment with rituximab, mycophenolate mofetil and azathioprine decreased (all P <0.05) and there was no statistically significant difference in the annual relapse proportion among the groups ( P =0.307). Conclusions: The most common clinical attack of first and all of MOGAD in children is ADEM, and the most common clinical syndrome is NMOSD. Rituximab, mycophenolate mofetil and azathioprine can reduce the annual relapse rate, but it is not clear effect of which treatment is better.