Effects of prednisone and plasma exchange on cognitive impairment in Hashimoto encephalopathy

The proposed pathophysiologic mechanism in Hashimoto encephalopathy (HE) is an autoimmune reaction to antigens shared by the thyroid gland and the CNS with possible immune complex deposition and subsequent cerebral dysfunction. Such an antibody-mediated process might respond to plasma exchange (PE). The standard treatment for HE is high-dose IV steroid therapy, often yielding good results.1 However, sometimes encephalopathy is refractory to steroid treatment or steroid side effects cannot be tolerated. We describe positive and negative effects of two alternative treatments of HE, oral prednisone and PE, in a 54-year-old woman. We sought to quantify the effects of oral prednisone and PE on cognition with neuropsychological testing before and after each intervention. A 54-year-old woman with a history of hypothyroidism presented to our clinic with progressive cognitive impairment and gait incoordination. Her …