Osmotic demyelination syndrome diagnosed by Magnetic Resonance Imaging in a child with tetraplegia: Case report.

Osmotic demyelination syndrome (ODS) is a rare acute demyelinating process that typically develops within days following osmotic stress. Although most commonly associated with the rapid correction of hyponatremia, chronic hypernatremia has also been reported as an etiological factor. Herein, we present a 16-year-old female patient who developed ODS secondary to electrolyte imbalance following treatment for acute myeloid leukemia (AML). Brain Magnetic Resonance Imaging (MRI) plays a pivotal role in enabling accurate diagnosis. Due to the involvement of both upper motor neurons (UMN) and lower motor neurons (LMN), this case represents a rare pediatric presentation with coexisting UMN signs and electrophysiologic LMN involvement.