Effective treatment of osmotic demyelination syndrome with plasmapheresis: a case report and review of the literature.

Background: Treatment options for chronic osmotic demyelination syndrome are limited to case reports and only a very few show complete recovery. We report a case of complete recovery of chronic osmotic demyelination syndrome with plasmapheresis.

Case Presentation: A 43-year-old Sri Lankan man presented with fever, repeated vomiting, unsteady gait, increased tonicity of his right upper limb and paucity of speech for three days. He was treated in the local hospital with antibiotics and antivirals as per central nervous system infection. He had hyponatraemia, which was rapidly corrected with hypertonic saline from 97 to 119 mmol/L. He was transferred to our hospital because of progressive reduction of consciousness, rapidly worsening rigidity and bradykinesia of all four limbs and worsening dysarthria and bradyphrenia. Magnetic resonance imaging of the brain was compatible with osmotic demyelination syndrome. He was commenced on plasmapheresis twenty-two days after rapid correction of sodium. He regained independent mobility with complete resolution of rigidity, bradykinesia and speech dysfunction after five cycles of alternate day plasmapheresis.

Conclusion: Plasmapheresis can be considered as an effective treatment modality in chronic osmotic demyelination syndrome.