Clinical and epidemiological characterization of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) in a tertiary center in Amazonas

Background: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is the most recently characterized inflammatory disorder of the central nervous system (CNS). It is a demyelinating disease in which an inflammatory response targets this glycoprotein, which is uniquely present on the surface of CNS myelin sheaths. Clinical presentation is diverse and includes optic neuritis, myelitis, brainstem syndrome, acute disseminated encephalomyelitis (ADEM), and FLAIR-hyperintense lesions in anti-mog associated encephalitis with seizures (FLAMES). Diagnosis is made based on compatible clinical and radiological findings, along with the presence of anti-MOG IgG in serum or cerebrospinal fluid. Objective: To characterize cases diagnosed with MOGAD managed at the Getúlio Vargas University Hospital of the Federal University of Amazonas (HUGV/Universidade Federal do Amazonas). Methods: A retrospective study was conducted by reviewing the medical records of patients diagnosed with MOGAD between 2019 and 2024. Results: 6 cases of MOGAD managed by the service were identified during the study period, with 4 cases presenting initially after the age of 20 years. One case occurred in a 7-year-old child. There was no gender difference in the distribution of cases. The most common presentations were optic neuritis, myelitis, and optic neuritis associated with myelitis, with only 1 case of ADEM. Only 1 patient had a preceding infection before symptom onset, and none had been vaccinated in the days preceding the onset. None of the patients had associated autoimmune diseases. All patients showed hyperintense lesions on T2-weighted MRI, and all received acute phase treatment, albeit delayed, as well as ongoing chronic immunosuppression. Five cases experienced symptom recurrence, with myelitis being the most common recurrent clinical presentation. Conclusion: Given the recent recognition of MOGAD as a distinct clinical entity, it is crucial to characterize identified cases in different populations. In our study population, a notable finding was that recurrence predominantly manifested as myelitis, contrasting with current literature that mentions optic neuritis as the primary recurrent presentation. Further studies are needed to confirm this characteristic.