Recurrent Hashimoto's encephalopathy, showing spontaneous remission: a case report.

Hashimoto's encephalopathy (HE) is a rare condition associated with Hashimoto's thyroiditis (HT). It is characterized by neurological/psychiatric symptoms, high levels of anti-thyroid antibodies, non-specific radiological examinations or electroencephalogram abnormalities, and responsiveness to corticosteroid treatment. We describe the case of a man with HE who showed decreased mentality, cognitive impairment, dysarthria, and gait disturbance. The initial attack was improved rapidly by corticosteroid treatment. When the symptoms recurred in 7 months, the patient achieved spontaneous remission without corticosteroid treatment. The recognition of the condition was essential for the prognosis and treatment of this rare disease.