Objective: To study the humoral immune response directed at myelin oligodendrocyte glycoprotein (MOG)in pediatric patients with isolated and recurrent optic neuritis(ON).
Design: Observational prospective case series.
Setting: Six pediatric hospitals in Germany and Austria.
Patients: Thirty-seven patients 18 years or younger with single or recurrent episodes of ON were recruited from 6 different hospitals.
Main outcome measures: Clinical features, magnetic resonance imaging findings, intrathecal IgG synthesis,and outcome were recorded. A live cell–based immunofluorescence assay was used to measure serum IgG antibodies to MOG and aquaporin 4.
Results: A single episode of ON was observed in 10 patients,and 15 experienced 2 to 12 episodes. The acute episode of ON was part of a clinically isolated syndrome in 12 patients, of whom 8 were subsequently classified as having multiple sclerosis. High-titer serum MOG-IgG antibodies (1:160) were detected in 17 patients (46%).In addition, high titers of MOG-IgG antibodies were more frequently observed in 12 of the 15 patients with recurrent episodes of ON (80%; median titer, 1:640)compared with 2 of the 10 patients with monophasic ON(20%; median titer, 0) and 3 of the 12 patients with ON as part of a clinically isolated syndrome (25%; median titer, 0).
Conclusion: High-titer MOG-IgG antibodies are predominantly detected in pediatric patients with recurrent ON, indicating that anti-MOG-specific antibodies may exert a direct role in the pathogenesis of ON in this subgroup.