Pontine and extrapontine osmotic myelinolysis after the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) associated with fluoxetine - Case report

Osmotic demyelination syndrome (ODS) may be precipitated by aggressive correction of a hypo or hyper-osmolar states. We describe the,case of a 53-year-old woman that was started on fluoxetine 20 mg/day for depression and nine days later was found to have fluoxetine-induced syndrome of inappropriate secretion of antidiuretic hormone. After hyponatremia correction the mental status of the patient gradually improved, but subsequently she had intermittent difficulty in speaking, naming objects, memory deficits and psychomotor slowness. Magnetic resonance revealed bilateral symmetric hyperintense lesions in the basal ganglia, temporal lobe and hippocampal formation compatible with ODS. These symptoms gradually resolved and she was discharged home without any deficits. Two months later, a new image showed lesion in pons and the other lesions had disappeared. Fluoxetine therapy had never been related with a complication like that.