Acute Disseminated Encephalomyelitis (ADEM) After Consecutive Exposures to Mycoplasma and COVID Vaccine: A Case Report.

Acute disseminated encephalomyelitis (ADEM) is an autoimmune demyelinating disease of the central nervous system, commonly triggered by viral infections or after immunization. ADEM occurrences in adults are rare. Full spectrum of complications is unknown for novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccines. A previously healthy 44-year-old female presented to the emergency room (ER) with acute onset of tingling, numbness, and weakness of both lower extremities, urinary retention, blurred vision in right eye, and midline lower back pain. Physical examination revealed bilateral lower extremity weakness 1/5, absent deep tendon reflexes, and decreased sensation. She received the first dose of SARS-CoV-2 vaccine six days prior to presentation to ER. Imaging of her lumbar spine and head were consistent with an active demyelinating plaque consistent with demyelinating disease either multiple sclerosis (MS) or ADEM. The patient was started on SoluMedrol 500 mg IV twice daily for five days. Serological workup and CSF analysis were nonsignificant except for IgM, elevated myelin basic protein, and positive IgG, IgA, and IgM. Patient gradually improved and was transferred to rehabilitation. Repeat MRI brain and spine showed improvement in previous lesions. However, she had worsening left eye symptoms that prompted her transfer to another facility for plasmapheresis. Plasma exchange was done for five treatments for ADEM. Patient started noticing improvement in vision and was discharged on steroid taper. We report a case of a possible association between ADEM and SARS-CoV-2 mRNA vaccine. It should be considered in the differential diagnosis in any case suggestive of acute demyelination after COVID-19 vaccination.