To investigate the clinical characteristics of myelin oligodendrocyte glycoprotein antibody associated disorders (MOGAD) combined with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis.

Sixty-five patients with MOGAD and 96 patients with anti-NMDAR encephalitis, admitted to our hospital from July 2018 to June 2021, were chosen in our study; 8 patients with MOGAD combined with anti-NMDAR encephalitis were selected as antibody double positive group; 21 patients with MOG antibody(+)/anti-NMDAR antibody(-) and 37 patients with anti-NMDAR antibody(+)/MOG antibody(-) were selected as controls. The differences of clinical characteristics of patients among these groups were compared.

(1) In these 8 patients from antibody double positive group, MOGAD and anti-NMDAR encephalitis occurred simultaneously in 6 patients, and anti-NMDAR encephalitis occurred prior to the episode of MOGAD in 2 patients. Autoimmune encephalitis was the dominant phenotype and demyelinating symptoms occurred in some patients. Both MOG antibody and anti-NMDAR antibody were detected in these 8 patients. MRI showed that lesions mostly involved in the cortex and subcortical white matter. Intravenous administration of high-dose methylprednisolone and immunoglobulin was given for patients at acute stage; two patients received mycophenolate mofetil treatment additionally during recurrence. After treatment, syndromes in these 8 patients got improvement. (2) There were no significant differences between patients from antibody double positive group and MOG antibody(+)/anti-NMDAR antibody(-) group in clinical manifestations, auxiliary examinations or treatments (P>0.05). As compared with patients in antibody double positive group, patients in the anti-NMDAR antibody(+)/MOG antibody(-) group had significantly lower proportion of children and significantly higher modified Rankin scale (mRS) scores at the height of their illness (P<0.05). As compared with patients in the MOG antibody(+)/anti-NMDAR antibody(-) group, patients in the anti-NMDAR antibody(+)/MOG antibody(-) group had significantly older onset age, significantly lower proportion of children, significantly higher proportion of patients with epilepsy and abnormal psychiatric behavior, significantly higher proportion of patients admitted to Intensive Care Unit, statistically higher mRS scores at the height of their illness, significantly lower proportion of patients with intracranial lesions, and significantly higher proportion of patients used immunoglobulin and plasma exchange (P<0.05).

MOG antibody and anti-NMDAR antibody can cause different clinical symptoms; when MOGAD patients have unusual symptoms, such as abnormal psychiatric behavior and epilepsy, or anti-NMDAR encephalitis patients develope demyelinating features, the possibility of MOGAD combined with anti-NMDAR encephalitis should be considered.

Myelin oligodendrocyte glycoprotein; N-methyl-D-aspartate; Encephalitis