Manifestation of Hashimoto's Encephalopathy with Psychotic Signs: a Case Presentation

Hashimoto's encephalopathy (HE) is a rare autoimmune disease with unclear pathophysiology, developing on the basis of Hashimoto's thyroiditis (HT), associated with antithyroid antibodies, that presents with autoimmune, neuroendocrine, and neuropsychiatric findings. The disease is characterized by generalized or focal slowing in the EEG, elevated antithyroid antibody titration in the serum, elevated cerebrospinal fluid protein level, and the presence of antithyroid antibodies. HE is known as an autoimmune disorder of the central nervous system. With this feature, it is differentiated from cognitive alterations observed in hypothyroidism or hyperthyroidism. The response to treatment with corticosteroids in line with the autoimmune nature of HE supports this diagnosis. This report shows a case presenting with neuropsychiatric symptoms, elevated antithyroid antibody titration in the serum, and complete response to steroid therapy. A clear indicator for the diagnosis of HE has not yet been found. Therefore, other potential causes need to be considered in the differential diagnosis of this clinical picture until they can be excluded after investigations. With this case report, we want to emphasize that in differential diagnosis of patients presenting with a variety of neuropsychiatric symptoms, Hashimoto's encephalopathy - though being seen quite rarely - should not be disregarded, given the dramatic improvement of patients receiving a correct diagnosis and appropriate treatment.