Clinical and radiological improvement of oligodendrocyte myelin syndrome with combined treatment of rituximab and plasmapheresis

Case presentation: Female patient, 22 years old, started in 2015 with paresthesia in the left lower limb. At time she didn‘t have her symptoms evaluated by a neurologist. Her symptoms were considered to be of psychogenic origin, and she was treated with an anxiolytic drug. In 2019, the patient developed bilateral optic neuritis (ON) and was referred to a neurology service. She underwent magnetic resonance imaging (MRI) which showed several demyelinating lesions, as well as a positive oligoclonal band. Her optical coherence tomography showed bilateral changes. She underwent intravenous methylprednisolone 1000mg per day for five days, with slight clinical improvement, repeating the treatment after a month. The patient was initially diagnosed with multiple sclerosis (MS). Interferon was started and, despite this, progressed to recurrent optic neuritis outbreaks and sensory and motor symptoms. The new MRI shows disseminated demyelinating lesions in the spinal cord. Antibody - aquaporin-4 (anti-aqp4) and myelin oligodendrocyte glycoprotein andibody (anti-MOG) research was performed (cell base assay method) and showed a negative anti-aqp4 antibody and positive anti-MOG. The patient, while using interferon, developed tetraparesis, spasticity in the lower limbs, worsening gait, requiring a wheelchair. After confirming the positivity of the anti-MOG, the patient underwent plasmapheresis (twice a year) and the use of rituximab, showing significant improvement in his gait (walking more than 100 m with a walker) and reducing spasticity after one year of treatment. Discussion: Myelin oligodendrocyte glycoprotein (MOG) is present on the surface of oligodendrocytes and the myelin sheath of the nervous system and the MOG antibody-associated disease (MOGAD) is the most recently studied inflammatory demyelinating disease of the central nervous system. The presence of MOG antibodies was found in a small portion of a group of patients with multiple sclerosis, with a more severe disease course, with higher rates of recurrence and no therapeutic response to disease-modifying therapies. Typical symptoms of MOGAD include ON and myelitis, which overlap with MS and neuromyelitis optica (NMO). In profile of the patient, MOGAD has less sex or age predilection than MS or NMO. The above patient presented reduced clinical and radiological activity with concomitant treatment with rituximab and plasmapheresis Final comments: The case presented in this article shows a female patient that had the MS diagnosis but the latest investigation showed anti-mog positive. Thus, the anti-MOG research shows it importance in cases of MS with non responsive treatment. In Brazil we have limited access to this type of exam, making diagnostic confirmation difficult. There is no specific medication to treat this disease. Treatment with rituximab and plasmapheresis for the patient resulted in clinical and radiological improvement.