Clinical characteristics and prognosis of myelin oligodendrocyte glycoprotein antibody-seropositive paediatric optic neuritis in China

Background/Aims To investigate clinical characteristics and prognosis of paediatric optic neuritis (PON) in patients seropositive for myelin oligodendrocyte glycoprotein antibody (MOG-Ab) in China. Methods Children displaying initial onset of optic neuritis (ON) were recruited from the Neuroophthalmology Department in the Chinese People's Liberation Army General Hospital from January 2016 to August 2017. They were assigned into three groups based on antibody status: MOG-Ab-seropositive ON (MOG-ON), aquaporin-4 antibody-seropositive ON (AQP4-ON) and double seronegative ON (seronegativeON). Results Totally 48 patients were assessed, including 25 MOG-ON (52.1%), 7 AQP4-ON (14.6%) and 16 seronegative-ON (33.3%). The MOG-ON and seronegative-ON cohorts had equal ratios of female/male, but the AQP4-ON cohort was predominantly females (100%). The patients with MOG-ON were significantly younger at onset compared with the AQP4-ON group. Of the MOG-ON eyes, 97.6% had good recovery of visual acuity (VA) (>= 0.5) compared with33.3% of AQP4-ON eyes (p< 0.001). However, there was no significant difference compared with the seronegative-ON eyes (82.6%, p=0.052). Two children in the MOG-ON group ended up being diagnosed with acute disseminated encephalomyelitis, while only one patient in the AQP4-ON group developed neuromyelitis optica during follow-up. Patients with MOG-ON had thicker peripapillary retinal nerve fibre layers overall and in the superior and inferior quadrants than in patients with AQP4-ON (p=0.005, p=0.002 and p=0.024, respectively). In addition, the macular ganglion cellinner plexiform in MOG-ON eyes became significantly thicker than in AQP4-ON eyes (p=0.029). Orbital MRI revealed a larger proportion of patients with MOG-ON had intracranial optic nerve involvement than patients with seronegative-ON (51.2% vs 17.4%, p=0.009). Conclusion MOG-ON was the most common PON subtype in China. MOG-ON had different clinical features including earlier age of onset, equal female/male ratio, better recovery of VA and thicker peripapillary retinal nerve fibre and macular ganglion cell-inner plexiform layers. MOG-Abs may be a potential biomarker for determining visual prognosis with PON.