Treatment of steroid-unresponsive tumefactive demyelinating disease with plasma exchange

To the Editor: The case presented by Mao-Draayer et al.1 highlights the potentially beneficial action of plasma exchange (PE) in acute demyelinative lesions of the CNS not responding to high-dose IV corticosteroids. Here we report another case history emphasizing the role of PE as a powerful second line treatment in acute demyelinating myelitis. A 32-year-old woman presented with a 4-week history of progressive motor weakness and painful dysesthesias of the right arm and leg. Neurologic examination revealed a 3/5 weakness of extensors and flexors of the right hand, sinking of the right leg, ipsilateral loss of proprioception, and a sensory level at C6. MRI of the cervical spinal cord demonstrated a hyperintense, gadolinium-enhancing dorsolateral lesion at C6/C7 (figure, left). Diagnostic …