A Case of Probable Creutzfeldt-Jakob Disease with Coexistence of the Features of Hashimoto Encephalopathy

Hashimoto encephalopathy shares common clinical features with Creutzfeldt-Jakob disease and must be regarded as a differential diagnosis because of its good prognosis. We report a case of Hashimoto encephalopathy, which had not been recognized before the diagnosis of Creutzfeldt-Jakob disease. The electroclinical findings were compatible with probable Creutzfeldt-Jakob disease and coexistence of Hashimoto thyroiditis was supported by high titers of anti-thyroid microsomal antibody and cytopathologic findings. Hashimoto encephalopathy was not improved, which was most likely due to the coexistence of Creutzfeldt-Jakob disease.