Voltage-gated potassium channel antibody-associated encephalitis with basal ganglia lesions

Abstract

Antibodies reactive with neuronal voltage-gated potassium channels (VGKCs) have been reported in patients with limbic encephalitis, which affects the medial temporal lobes and is characterized by subacute onset of temporal lobe seizures, memory impairment, and personality changes.1–5 MRI of those patients showed only abnormal signal intensity located in the medial temporal lobes.1–5 We describe a patient with encephalitis associated with anti-VGKC antibody who had MRI abnormalities localized in the basal ganglia as well as in the medial temporal lobes that improved dramatically on corticosteroid treatment. A previously healthy, 23-year-old woman presented with a generalized seizure and was admitted to a nearby hospital, 2 months after onset of repeated short-term fevers with cervical lymphadenopathy. She showed disorientation and memory loss. Brain CT was negative. A CSF examination showed pleocytosis (12 lymphocytes/mm3) and a normal protein level. Viral encephalitis was diagnosed, and she was prescribed IV acyclovir. She continued to show severe memory loss and childishness. Brain MRI done 17 days after admission showed symmetric abnormal signal intensities localized in the bilateral …