[A case of focal encephalitis with psychological symptoms similar to chorea minor].

We reported a patient with choreic movements, emotional lability, and compulsive-obsessive behavior that developed 4 weeks after onset of fever and lasted for several years. There was no evidence of streptococcal infection or rheumatic fever. T2-weighted MRI showed hyperintense lesions in the bilateral caudate nuclei and putamina. A diagnosis of focal encephalitis was made according to initial fever, convulsion, and CSF pleocytosis. Treatments with haloperidol and prednisolone were effective in some degree. The neurobehavioral syndrome as well as the involuntary movements in this patient can be attributed to the striatal damage, which may disrupt the basal ganglia-limbic-frontal lobe tracts. A symptomatic similarity between the syndrome in this patient and chorea minor suggests a striatal damage in chorea minor, where the causative lesions remain unknown.