Patients were involved if they were younger than 18 years old and met the diagnostic criteria of MOGAD proposed by Jarius S et al., defined as 1) Monophasic or relapsing acute optic neuritis (ON), myelitis, brainstem encephalitis, or encephalitis, or any combination of these syndromes; 2) MRI or electrophysiological (VEP in patients with isolated ON) findings compatible with CNS demyelination; 3) Seropositivity for MOG-IgG as detected using a cell-based assay employing full-length human MOG as target antigen (8). Here, MOG is linked to viral encephalitis.