Transient Myelin Oligodendrocyte Glycoprotein Antibody-positive Acute Disseminated Encephalomyelitis Following Influenza A Infection: A Rare Case.

Acute disseminated encephalomyelitis (ADEM) is an uncommon disease generally with a preceding history of infectious illness. Here, we report a rare case of ADEM following influenza A infection with transient detection of anti-myelin oligodendrocyte glycoprotein (MOG) antibody in a young male patient who presented with extensive demyelination of brain and spinal cord, likely the result of dysregulated immune response from previous influenza A infection. The patient presented to the emergency with urinary retention and progressive ascending weakness of lower limbs. Magnetic resonance imaging (MRI) of the brain and spinal cord showed multiple ill-defined hyperintensities, suggestive of demyelination. The clinical presentation, MRI findings, cerebrospinal fluid examination, negative anti-aquaporin-4 antibody and metabolic and other viral infectious screening supported the diagnosis of ADEM. The patient had transiently positive anti-MOG antibodies (for 3 months) and was treated with intravenous immunoglobulin followed by oral prednisolone for 3 months. There was a significant recovery in the upper limb weakness and brainstem function. This case highlights the association of anti-MOG antibody with ADEM following viral infections and the need for prolonged follow-up to differentiate between transient antibodies from relapsing MOG antibody disease.