Background: Hashimoto’s encephalopathy (HE) is a debilitating manifestation of
an autoimmune reaction against the thyroid that rarely can present with prominent psychiatric
symptoms. It is often under-diagnosed primarily due to its variety of symptoms as well as
a lack of definitive diagnostic criteria.
Methods: We report the case of a 13-year-old girl who was diagnosed with HE after presenting
with recurrent and severe psychosis with fever and a thyroidopathy. The patient had
prominent visual hallucinations and paranoid delusions. Between episodes, the patient did
not show evidence of psychiatric symptoms. This patient struggled with several incorrect diagnoses
and treatments for two years before the correct diagnosis of HE was made and displayed
marked improvement upon corticosteroid administration.
Discussion: This case illustrates the importance of increasing awareness of HE as well as
including HE in a differential diagnosis when paediatric patients present with psychosis and