Acute disseminated encephalomyelitis (ADEM) is a rare, immune-mediated demyelination of the central nervous system (CNS) affecting 0.64 per 100,000 people per year. This case report presents a 19 year-old male collegiate athlete who presented with paraplegia, diminished vibration and pinprick, diplopia, hyperreflexia and urinary retention following an upper respiratory infection one week prior to presentation. MRI of the brain and spinal cord showed T2 FLAIR hyperintensities in the pons, left middle cerebral peduncle, left insula, and right posterior frontal lobe. Extensive T2 FLAIR changes were noted in the cervical and thoracic cord. A punctuate area of enhancement at C5/C6 was also noted. CSF studies showed 340 white blood cells, 10 red blood cells, 78 protein and 57 glucose. Notably, serum Mycoplasma antibodies were positive, but were not detected in the CSF. Neuromyelitis optica aquaporin-4 antibodies and multiple sclerosis panel were negative. The patient was treated with doxycycline for 14 days and intravenous methylprednisolone alternating with plasmapheresis, followed by an oral prednisone taper. He did require brief intubation, but after a prolonged rehabilitation course, he was able to return to playing collegiate sports with minimal residual neurologic deficits.

CNS complications of Mycoplasma pneumoniae occur in less than 0.1% of infections and can be severe, as demonstrated by this case. The exact pathogenesis of M. pneumoniae CNS infections is not well understood, but is thought to be secondary to direct infection with cytokines causing neuronal tissue damage, indirect autoimmunity, vasculitis, thrombosis, or a combination of these. This case was felt to represent ADEM given the distribution of lesions on MRI, response to therapy, and overall improvement of lesions with no new lesions on follow up imaging. A component of direct infection contributing to the severity of his presentation cannot be fully ruled out.