# Clinical characteristics of MOG antibody-positive anti-NMDAR encephalitis: a single-center retrospective study

## TL;DR

This study compares clinical features of anti-NMDAR encephalitis patients with and without MOG antibodies, finding higher male prevalence and distinct symptoms in the MOG-positive group.

## Contribution

The study identifies unique clinical markers in MOG antibody-positive anti-NMDAR encephalitis patients, aiding in diagnosis and treatment strategies.

## Key findings

- MOG-Ab (+) patients had significantly higher male prevalence (87.5% vs. 40%).
- MOG-Ab (+) patients showed more headaches, elevated CSF-WBC counts, and MRI abnormalities.
- MOG-Ab (+) patients had a higher recurrence rate (50% vs. 12.5%) within one year.

## Abstract

This study was designed to clarify the clinical characteristics of myelin oligodendrocyte glycoprotein (MOG) antibody-positive anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis.

This was a single-center retrospective study. Patients with anti-NMDAR encephalitis hospitalized at Tianjin Huanhu Hospital were included in the study. The observation group consisted of patients with anti-NMDAR encephalitis who tested positive for serum MOG-antibodies [MOG-Ab (+)], while the reference group included patients who tested negative for serum MOG-antibodies [MOG-Ab (–)]. Clinical data were collected from both groups and statistical methods were employed to analyze the differences between the two groups.

This study enrolled 48 patients (n = 48) with anti-NMDAR encephalitis, comprising eight cases (n = 8, 16.67%) in the MOG-Ab (+) group and 40 cases (n = 40, 83.33%) in the MOG-Ab (–) group. The proportion of male patients in the MOG-Ab (+) group was significantly higher than that in the MOG-Ab (–) group (87.50 vs. 40.00%, χ2 = 4.274, P = 0.039). Patients in the MOG-Ab (+) group frequently experienced headaches, which occurred more often than in the MOG-Ab (–) group (75.00 vs. 25.00%, χ2 = 5.419, P = 0.020). The median white blood cell (WBC) count in the cerebrospinal fluid (CSF) of the MOG-Ab (+) group was 125.00 (65.00, 155.00) × 106/L, representing a rate that is 12.5 times higher than that of the MOG-Ab (–) group, indicating more pronounced immune inflammatory response in the CSF of the MOG-Ab (+) group (Z = −3.320, P = 0.000). Additionally, the MOG-Ab (+) group exhibited a higher proportion of leptomeningeal enhancement (37.50 vs. 2.50%, P = 0.012) and cortical lesions (87.50 vs. 40.00%, χ2 = 4.274, P = 0.039) on MRI. Recurrence occurred in 50.0% of patients in the MOG-Ab (+) group within 1 year of discharge follow-up, compared to only 12.50% in the MOG-Ab (–) group (χ2 = 3.938, P = 0.047).

For patients with anti-NMDAR encephalitis presenting with headaches, if there is a significant increase in CSF-WBC count, coupled with abnormal MRI signals in the leptomeninges or cortex, it is recommended to test for MOG antibodies. This is particularly crucial for male patients. For those with positive double antibodies, more aggressive long-term immunosuppressive therapy may be necessary to prevent recurrence.