[Clinical and imaging characteristics and influencing factors of myelin oligodendrocyte glycoprotein antibody-associated disease with different IgG antibody conversions].

To investigate the clinical and imaging characteristics of patients with myelin oligodendrocyte glycoprotein antibody (MOG-IgG)-associated disease (MOGAD) with different MOG-IgG seroconversions, and to analyze the factors affecting the conversion. Retrospective study. Patients diagnosed with MOGAD in the Department of Neurology, Beijing Tongren Hospital, Capital Medical University from January 2019 to April 2023 were included and the follow-up ended in May 2024. The clinical and imaging characteristics of MOG-IgG negative conversion group and non-negative conversion group were compared. A multivariate logistic regression model was used to analyze the influencing factors of MOG-IgG negative conversion. A total of 51 patients were enrolled, including 23 males and 28 females, aged (38.3±16.4) years. There were 14 cases (27.5%) in the negative conversion group and 37 cases (72.5%) in the non-negative conversion group. The proportion of patients with initial serum MOG-IgG titer<1∶100 (10/14) and the proportion of patients with first attack (11/14) at the inception in the negative conversion group were higher than those in the non-negative conversion group [40.5% (15/37), 21.6% (8/37), <0.05]. The annual relapse rate (ARR) of the negative conversion group was [(, )]0 (0, 0.2) and was significantly lower than that of the non-negative conversion group 0.5(0.1, 1.0) (=0.001). No spinal cord involvement was found in the clinical classification and imaging of the negative conversion group, and 7/14 of the optic nerve MRI was only involved in the intraorbital segment, which was higher than that of the non-negative conversion group [13.5%, (5/37), =0.018]. The median follow-up time was 18.1 (14.3, 37.3) months, and the median time from initial onset to serum MOG-IgG negative was 4.5 (2.8, 11.5) months in the negative conversion group, two cases in the negative conversion group relapsed after continuous negative conversion, one case relapsed with MOG-IgG positive and the other with negative. The first attack at the inception (=86.788, 95%: 1.436-5 244.198, =0.033) and the low initial serum MOG-IgG titer (=10.840, 95%: 1.239-94.845, =0.031), the more likely MOG-IgG seroconversion would be negative. Only the orbital segment of the optic nerve involvement without spinal cord involvement was more common in patients with MOG-IgG negative conversion. MOGAD patients with a first clinical attack and low initial MOG-IgG titer were more likely MOG-IgG seroconversion negative.