Background Hashimoto encephalopathy is a potentially fatal condition associated with a presentation of myoclonus, altered conscious state, strokelike episodes, rapid cognitive decline, and neuropsychiatric symptoms. Both congenital hypothyroidism and acquired hypothyroidism are common in patients with Down syndrome.
Objective To describe the presentation of Hashimoto encephalopathy in patients with Down syndrome.
Design Clinical case reports.
Setting General neurology unit.
Patients Two Down syndrome patients diagnosed as having Hashimoto encephalopathy are described.
Intervention High-dose oral corticosteroids.
Main Outcome Measures Neurologic examination, electroencephalography, and blood analysis results.
Results Both patients responded to treatment, with a slow return to their premorbid level of function.
Conclusion Hashimoto encephalopathy should be considered in Down syndrome patients with rapidly progressive cognitive decline.
