[Clinical features of anti-myelin oligodendrocyte glycoprotein antibody-associated diseases in children with cortical encephalitis].

Objective: To describe the clinical features of anti-myelin oligodendrocyte glycoprotein (MOG) antibody-positive cortical encephalitis in children. Methods: Patients who were hospitalized in Beijing Children's Hospital from June 2018 to October 2019, with positive MOG antibodies and phenotype of cortical encephalitis were retrospectively analyzed. Cell-based assays (CBAs) were used to test MOG antibodies. Results: Five patients had the phenotype of cortical encephalitis during follow-up, with 3 females and 2 males. The age of onset ranged from 8 years to 12 years and 1 month. At the last follow-up, 3 cases exhibited a monophasic course and 2 cases were with relapse and remission courses. Six out of 8 episodes which had the phenotype of cortical encephalitis presented with seizures, among which 3 episodes had status epilepticus. None had recurrent seizures during remission. Other symptoms included fever (7/8), headache and vomiting (4/8), somnolence (3/8) and hemiplegia (1/8). Unilateral cortical swelling was observed in cerebral magnetic resonance imaging (MRI) of all patients, without any hemorrhage and necrosis. White blood cell (WBC) counts of cerebrospinal fluid increased, ranging from8×10(6)/L to 186×10(6)/L. All patients recovered well after treatment with intravenous immunogloblin and glucocorticoid. Two patients had relapses during follow-up and were additionally treated with mycophenolate mofetil. Conclusions: Anti-MOG antibodies can induce cortical encephalitis. In clinical setting, fever, headache and seizures are common, however, severe consciousness disturbance and local neurological deficits are rare in these patients. Cerebral MRI shows unilateral cortical swelling without any hemorrhage and necrosis. Usually, immunotherapy works well. No patients exist repeated seizures in remission, but some patients may have relapses.