Benign course of central pontine myelinolysis in a patient with anorexia nervosa

Central pontine myelinolysis is a rare neurologic disorder defined by symmetric demyelination of the central base of the pons. Until recently its outcome was considered invariably poor if not fatal. We report a 15-year-old female patient with severe anorexia nervosa who acutely developed a locked-in syndrome. Magnetic resonance imaging revealed a central pontine lesion. There was no serum sodium abnormality. The corticospinal and corticonuclear tracts were intact, as assessed by serial neurophysiologic studies. Finally, the patient recovered completely both clinically and radiologically. This article discusses these observations in the light of recent reports on similar benign outcomes of central pontine myelinolysis. Although electrolyte imbalances could be overestimated and the clinical significance of the radiologic lesion is uncertain, the functional assessment of the corticospinal and corticonuclear fibers might have prognostic value.