Rinsho Shinkeigaku (Clinical Neurology)

Case Report

Autoimmune encephalitis with anti-glutamate receptor antibody presentingas epilepsia partialis continua and action myoclonus: a case report

Yuji Kato, M.D.1), Yoshihiko Nakazato, M.D.1), Naotoshi Tamura, M.D.1), Ryo Tomioka, M.D.1), Yukitoshi Takahashi, M.D.2) and Kunio Shimazu, M.D.1)

1)Department of Neurology, Saitama Medical University
2)National Epilepsy Center, Shizuoka Institute of Epilepsy and Neurological Disorders

A 19-year-old man was admitted to our hospital with tremor and myoclonus that appeared after several episodes of consciousness disturbance and generalized convulsions. While steroid therapy resolved these symptoms, epilepsia partialis continua (EPC) and action myoclonus developed. Clobazam improved the EPC, but action myoclonus persisted. Oral tandospirone (30 mg/day) was given because 5-hydroxyindole acetic acid (5-HIAA) was markedly decreased in the cerebrospinal fluid (CSF). After 10 days of this therapy, most action myoclonus disappeared and he could perform fine motor skills. Although the MR structural images were unremarkable, cerebral SPECT showed decreased uptake in the left thalamus and bilateral frontal lobes. The antibody against glutamate receptor subunit &epsion;2 was positive in the CSF.
This is the first report of autoimmune encephalitis with anti-glutamate receptor antibody presenting as low level of 5-HIAA in the CSF. Tandospirone was effective for action myoclonus.

(CLINICA NEUROL, 47: 429|433, 2007)
key words: autoimmune encephalitis, anti-glutamate receptor antibodies, epilepsia partialis continua, action myoclonus, tandospirone

(Received: 16-Dec-06)