[Case with probable dementia with Lewy bodies, who shows reduplicative paramnesia and Capgras syndrome].

We report a case of probable dementia with Lewy bodies (DLB), showing reduplicative paramnesia (RP) and Capgras syndrome (CS). The patient, a right-handed 60 year-old male, began to show progressive dementia. At the age of 65, he showed fluctuating cognitive impairment and recurrent visual hallucinations. His SPECT demonstrated hypoperfusion not in the medial temporal cortices, but in the parieto-occipital lobes, where the right hemisphere was dominantly hypoperfused. He was diagnosed with probable DLB. In addition to recurrent visual hallucinations, he showed a sense of self- (or others) transfiguration, consciousness of something non-existent (Leibhaftige Bewusstheit; Jaspers, K.), and fluctuating visuo-spacial impairment. At the age of 67, he gradually complained of his duplicative wives "sosie". Finally he went so far as to talk about a nameless phantom boarder. We considered that RP and CS of this case comprised a sense of self-(or others) transfiguration, misidentification of important persons and places, and productive symptoms such as consciousness of something non-existent (Leibhaftige Bewusstheit) and visual hallucinations. The above mentioned symptoms might be originated not only from the disturbance of visuospacial recognition, which involves the limbic system (especially amygdala), medial frontal cortex, and right hemisphere of the brain, but also from the disturbance of recursive consciousness, due to diffusely damaged brain regions with Lewy body pathology. (Authors' abstract)