Hashimoto's encephalopathy
Hashimoto's encephalopathy, also known as steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT), is a neurological condition characterized by encephalopathy, thyroid autoimmunity, and good clinical response to corticosteroids. It is associated with Hashimoto's thyroiditis, and was first described in 1966.
Source: Wikipedia — Hashimoto's encephalopathy (CC BY-SA 4.0)