Osmotic demyelination syndrome associated with hypophosphataemia: 2 cases and a review of literature

Aim 
Central and extrapontine myelinolysis are collectively known as osmotic demyelination syndrome. This encephalopathic illness has been well documented in the adult literature, occurring most commonly in the context of chronic alcoholism, correction of hyponatraemia and liver transplantation. Aetiology and outcome in the paediatric population are less well understood. 

Methods 
Two cases of osmotic demyelination syndrome occurring in children with transient severe hypophosphataemia during the course of their illness are presented. Both had very different neurological outcomes, but the changes of central and extrapontine myelinolysis were apparent on neuroimaging. Sixty-one cases in the paediatric literature were then reviewed. 

Results 
We summarize aetiology and outcome in paediatric cases of osmotic demyelination syndrome and postulate a role for hypophosphataemia as a contributing factor in the development of these sometimes devastating conditions. 

Conclusion 
Hypophosphataemia may contribute to the risk of developing osmotic demyelination syndrome in at-risk paediatric patients and further study of this association should be undertaken.