[A case of chronic cerebellitis with anti-glutamate receptor delta 2 antibody]

A 1-year-8-month-old patient developed cerebellar ataxia following a prodromal infection. Despite initial diagnosis of acute cerebellar ataxia, his symptoms lasted for more than 30 days. High-dose intravenous immunoglobulin and steroid pulse therapy failed to ameliorate his cerebellar symptoms, which fluctuated in association with infections. At the age of 3 years and 8 months, he had mental retardation with cerebellar symptoms. Findings of MR imaging and single photon emission computed tomography were normal. Neuron-specific enolase of cerebrospinal fluid (CSF) ranged from 10.4-17.6 ng/ml, correlating with the cerebellar symptoms. Serum and CSF anti-glutamate receptor delta 2 antibodies were detected in the serum and CSF. We diagnosed him as having chronic cerebellitis associated with anti-glutamate receptor delta 2 antibody.