A Case of an Adult with Acute Disseminated Encephalomyelitis with Optic Neuritis Associated to Anti-Mog Antibody

Background: Acute disseminated encephalomyelitis (ADEM) is an immune mediated demyelinating disease of the central nervous system (CNS) with pediatric predilection. ADEM is characterized by a polyfocal clinical CNS event with encephalopathy and radiographic evidence of multifocal demyelination. The role of anti-myelin oligodendrocyte glycoprotein (anti-MOG) in the pathogenesis of ADEM is under controversy. ADEM followed by optic neuritis (ADEM-ON) has been introduced as a relapsing clinical phenotype associated with anti-MOG antibodies, with very few adults cases in the literature.  Herein, we report a case of an adult with ADEM-ON associated to anti-MOG. 

Objectives: To report a case of an adult with ADEM-ON associated to anti-MOG.

Methods: Case report and literature review

Results: A 45 year old woman with history of migraine headaches, asthma, depression and anxiety had subacute onset of headache, encephalopathy, nausea, vomiting, dysgeusia, dysosmia, decreased appetite, paresthesias, and sphincter dysfunction a month following influenza vaccine.  Initial brain MRI showed multifocal hyperintensities in the left temporal lobe, thalamus, and basal ganglia with areas of contrast enhancement.  Cerebrospinal fluid showed RBC <1 cells/mL, WBC: 17 cells/mL with 93% lymphocytes, protein: 78 mg/dL, glucose: 54 mg/dL.  PET scan, MRI of cervical and thoracic spine were normal.  A course of intravenous methylprednisolone and IVIG was given within two months with partial clinical and radiographic improvement.   At month fourth and fifth she had recurrent events of encephalopathy, headaches and right optic neuritis in the set of new radiographic activity.   Brain MRI showed new multifocal hyperintensities in the subcortical white matter, corpus callosum, brainstem and right pre-chiasm with areas of contrast enhancement.  Another course of IV methylprednisolone was given along with plasmapheresis with good clinical and radiographic response.   Anti-MOG was found positive in serum.  Long term treatment with oral corticosteroids and azathioprine was initiated with continued clinical and radiographic improvement.

Conclusions: ADEM-ON has been recognized as a demyelinating disease associated with anti-MOG. The pathogenetic role of anti-MOG antibodies in demyelinating disease is still not clear.  Some speculate it could be an epiphenomenon due to myelin destruction. A peripheral versus a central trigger for CNS autoimmunity has also been proposed. Regardless, patients with demyelinating disease associated to anti-MOG seem to have a distinct clinical, radiological and therapeutic profile.