Insights from Alberta's Cases: Investigating Myelin Oligodendrocyte Glycoprotein Antibody-Associated Optic Neuritis

Theme: Neuro-ophthalmology
What: Neuro-ophthalmology
Part of: Neuro-ophthalmology I / Neuro-ophtalmolgie I
When: 6/1/2024, 11:15 AM - 12:45 PM
Where: Room | Salle 714 B

Abstract

Purpose:

Myelin Oligodendrocyte Glycoprotein (MOG)-associated Optic Neuritis (ON) is an antibody-mediated demyelinating disease of the central nervous system (CNS). This relatively recent addition to the spectrum of CNS demyelinating disorders distinguishes itself from other CNS demyelinating diseases, such as Multiple Sclerosis and neuromyelitis optica spectrum disorder, in terms of its clinical presentation, treatment approach, and prognosis. This study aims to thoroughly investigate the demographics, clinical presentation, and treatment of patients with MOG-ON in Alberta by comprehensively examining patients who tested positive for the MOG autoantibody at Alberta’s centralized testing facility.

Study Design:

This retrospective study investigates patients who underwent fixed, cell-based MOG-IgG assays in the province of Alberta, conducted by MitogenDx through Alberta Precision Labs, from July 2017 to September 2022.

Methods:

In Alberta, MitogenDx through Alberta Precision Labs performs all MOG-IgG cell-based assays. A comprehensive review of the medical records of each patient who underwent this cell-based assay provided various data points for patients with a positive MOG-IgG titer. These included demographic information, initial symptoms, diagnostic investigations, principal diagnosis, treatment protocols, Neuroimaging findings, available Optical Coherence Tomography (OCT) data, and final visual acuity. Final diagnoses were carefully verified, and patients without confirmed final diagnoses were excluded.

Results:

Data analysis revealed that among 3,135 tested patients over approximately 5 years, 162 patients tested positive for MOG-IgG, resulting in a positivity rate of 5.2%. Of these, 79 (48.8%) presented with ON, with 43 (54.4%) females and 36 (45.6%) males. Of the 79 patients testing positive for MOG-IgG, 24 (30.4%) were highly positive, 17 (21.5%) were moderately positive, 32 (40.5%) were weakly positive, and 6 (7.6%) initially tested negative before seroconverting. Initial presentations ranged from 5.5 to 85.2 years, with an average age of 33.8 years. Ocular pain was reported in 74.5% of cases, with 35.5% presenting with bilateral optic neuritis. Additionally, 78.8% of patients displayed a relative afferent pupillary defect. Ocular examination and ancillary tests indicated a baseline best-corrected visual acuity ranging from light perception to 20/20, and OCT measured retinal nerve fiber layer values ranging from 59 to 422 µm. 

Conclusions:

This study represents the first comprehensive investigation of the demographic and clinical presentation of all confirmed MOG-ON cases within a defined time in a Canadian province. The data provides statistical evidence to guide clinical practice and prioritize investigations in the workup of ON. Continued analysis of follow-up data will delineate treatment efficacy and identify prognostic factors influencing visual outcomes.

Presenter(s)

Presenting Author: Abdullah Al-Ani

Additional Author(s):

Saerom Youn, McMaster University

Fiona Costello, University of Calgary

Jodie Burton, University of Calgary

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