Hashimoto encephalopathy and Down syndrome

Arch Neurol. 2009 May;66(5):663-6. doi: 10.1001/archneurol.2009.45.


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.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenal Cortex Hormones / administration & dosage
  • Brain / metabolism
  • Brain / pathology
  • Brain / physiopathology
  • Brain Diseases, Metabolic / drug therapy
  • Brain Diseases, Metabolic / genetics*
  • Brain Diseases, Metabolic / physiopathology*
  • Comorbidity
  • Disease Progression
  • Down Syndrome / drug therapy
  • Down Syndrome / genetics*
  • Down Syndrome / physiopathology*
  • Electroencephalography
  • Female
  • Genetic Predisposition to Disease
  • Hashimoto Disease / drug therapy
  • Hashimoto Disease / genetics*
  • Hashimoto Disease / physiopathology*
  • Humans
  • Magnetic Resonance Imaging
  • Middle Aged
  • Thyroid Gland / metabolism
  • Thyroid Gland / physiopathology
  • Thyroid Hormones / metabolism
  • Treatment Outcome
  • Young Adult


  • Adrenal Cortex Hormones
  • Thyroid Hormones