Hashimoto's encephalitis as a differential diagnosis of Creutzfeldt-Jakob disease

Objectives-During an epidemiological study of Creutzfeldt-Jakob disease in Germany, Hashimoto's encephalitis was encountered as a differential diagnos is, which has not yet been described in this context, Methods-The symptoms and findings of seven patients who fulfilled the crite ria for "possible" Creutzfeldt-Jakob disease are presented. Results-A Hashimoto's thyroiditis with antibodies against thyroglobulin or thyroid peroxidase, or both and a hypoechoic thyroid ultrasonogram were fou nd in all cases. Analysis of CSF disclosed an increased leucocyte count in three patients, and a raised CSF:serum concentration ratio of albumin (QAlb ) in four patients. The 14-3-3 protein, typical of Creutzfeldt-Jakob diseas e, could not be detected in any of our patients. No periodic sharp wave com plexes, which are typical of Creutzfeldt-Jakob disease, were detected on EE G in any of the cases. Ey contrast with Creutzfeldt-Jakob disease, which le ads to death within a few months, the patients with Hashimoto's encephaliti s often recover quickly when treated adequately. All the patients improved after administration of corticosteroids. Conclusion-The clinical symptomatology of both diseases may be very similar : dementia, myoclonus, ataxia, and personality change or psychotic phenomen a are characteristic symptoms.