460 - Multiple Sclerosis Causing Brown-Sequard Syndrome

Case Diagnosis: Multiple Sclerosis

Case Description: A 43-year-old male with no significant medical history presented to the hospital with subacute onset of right lower extremity weakness and left lower leg sensory changes; describing it as though his left leg is "in a hot tub”. Physical exam is notable for monoparesis of the right leg, altered pinprick/temperature sensation of the left leg below the knee, and decreased vibration sensation in the feet bilaterally. Hyperreflexia at the knee and ankle bilaterally with associated ankle clonus on the right were also noted. MRI of the cervical and thoracic spine revealed a T2 hyperintense signal in the right lateral cord at the T11-12 level. MRI of the brain revealed a periventricular active demyelinating lesion in addition to numerous other nonenhancing foci in the corpus callosum, frontal, parietal, and temporal lobes. The patient was started on IV methylprednisolone for a 3-day course with marked improvement in symptoms.

Discussions: Brown-Sequard Syndrome is a rare constellation of neurological findings resulting from a hemisection spinal cord injury. Ipsilateral neurological findings include weakness, diminished proprioception, and diminished vibratory sensation below the level of injury. Contralateral findings include altered pain and temperature sensation below the level of injury. Traumatic spinal cord injuries account for most Brown-Sequard lesions, however, non-traumatic causes such as stroke, tumor, infection, and inflammatory conditions have also been reported. In this specific patient, a brain MRI was promptly obtained after initial spine imaging was highly suspicious for a demyelinating condition. This led to an expeditated diagnosis, treatment plan, and subsequent improvement in his neurological deficits.

Conclusions: Although extremely rare, Brown-Sequard Syndrome can present as the initial manifestation of Multiple Sclerosis. In patients presenting with Brown-Sequard findings without obvious trauma, a wide differential diagnosis must remain that includes neuroinflammatory disorders.