Clinical and radiological spectrum of anti-myelin oligodendrocyte glycoprotein (MOG) antibody encephalitis: single-center observational study

Objective: The objective was to describe the clinical presentations, radiologic features, and outcomes of patients with autoimmune encephalitis associated with myelin oligodendrocyte glycoprotein antibody (MOG).

Background: During the past decade, the spectrum of the myelin oligodendrocyte glycoprotein antibody-associated diseases (MOGAD) has expanded. Recently, patients with MOG antibody encephalitis (MOG-E) who do not fulfill the criteria for ADEM have been reported. In this study, we aimed to describe the spectrum of MOG-E.

Methods: Sixty-four patients with MOGAD were screened for encephalitis-like presentation. We collected the clinical, radiological, laboratory, and outcome data of the patients who presented with encephalitis and compared it with the non-encephalitis group.

Results: We identified sixteen patients (nine males and seven females) with MOG-E. The median age of the encephalitis population was significantly lower than the non-encephalitis group (14.5 years (11.75-18) vs. 28 years (19.75-42), p = 0.0004). Twelve out of sixteen patients (75%) had fever at the time of encephalitis. Headache and seizure were present in 9/16 (56.2%) and 7/16 (43.75%) patients, respectively. FLAIR cortical hyperintensity was present in 10/16 (62.5%) patients. Supratentorial deep gray nuclei were involved in 10/16 (62.5%) patients. Three patients had tumefactive demyelination, and one patient had a leukodystrophy-like lesion. Twelve of 16 (75%) patients had a good clinical outcome. Patient with leukodystrophy pattern and other with generalized CNS atrophy showed a chronic progressive course.

Conclusion: MOG-E can have heterogeneous radiological presentations. FLAIR cortical hyperintensity, tumefactive demyelination, and leukodystrophy-like presentations are novel radiological presentations associated with MOGAD. Though majority of MOG-E have a good clinical outcome, few patients can have chronic progressive disease even on immunosuppressive therapy.