Abstract: Objective To explore the clinical features and prognosis of myelin oligodendrocyte glycoprotein (MOG) antibody-associated demyelinating disease in children. Methods The clinical data of MOG antibody-associated demyelinating disease in 57 children hospitalized from January 2014 to October 2019 were retrospectively analyzed, and the prognosis of the children who were followed up for more than 6 months was analyzed. Results In 57 children ( 28 boys and 29 girls) with a median onset age of 7 . 3 ( 5 . 2 - 10 . 5 ) years, 35 children ( 61 . 4 %) had precursor events such as infection or vaccination before onset. There were 45 cases ( 78 . 9 %) with intracranial hypertension, 43 cases ( 75 . 4 %) with fever, and 40 cases ( 70 . 2 %) with encephalopathy. Acute disseminated encephalomyelitis (ADEM, 49 . 1 %) was the most common clinical phenotype, and MOG antibody and anti-N-methyl-D-aspartate acid receptor (NMDAR) antibody coexisted in 5 cases (8.8%). The MOG antibody titer in serum was higher than that in cerebrospinal fluid, the difference was statistically significant (P< 0 . 05 ). Fifty-two children underwent head MRI, and the white matter ( 40 cases, 76 . 9 %), basal ganglia ( 27 cases, 51 . 9 %), and thalamus ( 22 cases, 42 . 3%) were more commonly affected. The scores of the extended disability status scale (EDSS) decreased after intravenous injection of IVIG and / or high-dose hormone therapy in most children during the acute phase, and the difference was statistically significant (P< 0 . 001 ). Twenty-nine children were followed up for more than 6 months, and 14 of them had relapsed. The fever at the first episode was more common, and more than 2 week interval between the onset and IVIG and / or hormonal impulse therapy were more commonly observed in relapsed children, the difference was statistically significant (P< 0 . 05 ). There is no clear correlation between serum MOG antibody titers and EDSS scores of children in the acute phase, and it could not accurately assess or predict the stability or relapse of the disease. Conclusion ADEM is the most common clinical phenotype of MOG antibody associated demyelinating disease in children. MOG antibodies can also co-exist with anti-NMDAR antibodies. IVIG and / or hormonal impulse therapy can effectively relieve the symptoms of disability in acute stage. Fever at first episode and more than 2 week interval between the onset and IVIG and / or hormone treatment may be related to relapse.

Key words: MOG antibody associated demyelinating disease; myelin oligodendrocyte glycoprotein; clinical feature; prognosis; child