[Non-herpetic acute limbic encephalitis-like manifestation in a case of Hashimoto's encephalopathy with positive autoantibodies against ionotropic glutamate receptor epsilon2].

A 37-year-old woman developed memory disturbance and seizures preceded by headache and high fever. Physical examination revealed persistent high fever, confusion, neck stiffness, anterograde and retrograde amnesia and disorientation. CSF showed pleocytosis and normal glucose level, and negative herpes simplex virus DNA on PCR. The fluid attenuated inversion recovery (FLAIR) MRI of the brain demonstrated nearly symmetric high signal intensity areas in the bilateral mesial temporal lobes. The tentative clinical diagnosis was non-herpetic acute limbic encephalitis (NHALE), and administration of methylprednisolone improved her conditions. Laboratory tests revealed mild hypothyroidism with high titers of serum antibodies against TPO and thyroglobulin, consistent with Hashimoto's disease. In addition, antibodies against amino terminal of alpha-enolase in the serum and those against glutamate receptor (GluR) epsilon2 in the serum and CSF were positive. A final diagnosis of Hashimoto's encephalopathy associated with GluRepsilon2 antibody was made. The present case suggests that NHALE-like clinical manifestation can be produced by autoimmune-mediated encephalopathies.