A case of acute cerebellitis accompanied by autoantibodies against glutamate receptor δ2

A 13-year-old boy presented with a six-day history of headache and gradually developed severe meningeal irritation symptoms. Brain magnetic resonance imaging revealed left cerebellar swelling and obstructive hydrocephalus. Then he showed transient ataxia, but recovered without any sequelae soon after high dose steroid therapy. IgG type of autoantibodies against glutamate receptor δ2 (GluRδ2) were detected in the serum, but not in the cerebrospinal fluid in his early clinical course. It was suggested that autoantibodies against GluRδ2 might not have injured the tissue due to the immunological action, but might be induced as a consequence of cerebellar damage. Early steroid treatment for acute cerebellitis might have been effective to prevent the progress of the disease and improve the prognosis.