Steroid-responsive encephalopathy associated with autoimmune thyroiditis

BMJ Case Rep. 2025 Sep 25;18(9):e268082. doi: 10.1136/bcr-2025-268082.

Abstract

Hashimoto encephalopathy or steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT) is a rare condition associated with rapidly progressive dementia, stroke-like symptoms, psychosis and positive antithyroid antibodies. In this case report, a woman in her 80s with hypothyroidism and no other medically relevant history presented with a 2-week complaint of progressive hallucinations, short-term memory loss and paranoia. Eventually hospitalised, her hospital course was complicated by severe hospital-acquired delirium, which clouded the clinical picture; however, initial workup revealed an elevated thyroglobulin antibody and thyroid peroxidase, both highly specific for SREAT. A 3-day course of high-dose methylprednisolone (1 g/day) was administered, which revealed marked improvement in patient symptoms. Definitive treatment included a 13-week oral prednisone taper and outpatient follow-up with neurology and primary care. In cases of new onset neuropsychiatric symptoms in geriatric populations, SREAT is a reversible, must-not-miss diagnosis, when treated with systemic steroids.

Keywords: Delirium; Memory disorders (psychiatry); Paraneoplastic Syndromes; Primary Care; Thyroid disease.

Publication types

  • Case Reports

MeSH terms

  • Aged, 80 and over
  • Brain Diseases* / diagnosis
  • Brain Diseases* / drug therapy
  • Brain Diseases* / etiology
  • Encephalitis
  • Female
  • Glucocorticoids / therapeutic use
  • Hashimoto Disease* / complications
  • Hashimoto Disease* / diagnosis
  • Hashimoto Disease* / drug therapy
  • Humans
  • Methylprednisolone* / administration & dosage
  • Methylprednisolone* / therapeutic use
  • Prednisone / therapeutic use
  • Thyroiditis, Autoimmune* / complications
  • Thyroiditis, Autoimmune* / diagnosis
  • Thyroiditis, Autoimmune* / drug therapy

Substances

  • Methylprednisolone
  • Glucocorticoids
  • Prednisone

Supplementary concepts

  • Hashimoto's encephalitis