A case of recurrent depressive disorder presenting with Alice in Wonderland syndrome: psychopathology and pre- and post-treatment FDG-PET findings

Background Alice in Wonderland syndrome (AIWS) is a rare neuropsychiatric syndrome that typically manifests in distortion of extrapersonal visual image, altered perception of one’s body image, and a disturbed sense of the passage of distance and time. Several conditions have been reported to contribute to AIWS, although its biological basis is still unknown. Here, we present the first case demonstrating a clear concurrence of recurrent depressive disorder and AIWS. The clinical manifestations and pre- and post-treatment fluorodeoxyglucose positron-emission tomographic (FDG-PET) images provide insights into the psychopathological and biological basis of AIWS. Case presentation We describe a 63-year-old Japanese male who developed two distinct episodes of major depression concurrent with AIWS. In addition to typical AIWS perceptual symptoms, he complained of losing the ability to intuitively grasp the seriousness of news and the value of money, which implies disturbance of high-order cognition related to estimating magnitude and worth. Both depression and AIWS remitted after treatment in each episode. Pre-treatment FDG-PET images showed significant hypometabolism in the frontal cortex and hypermetabolism in the occipital and parietal cortex. Post-treatment images showed improvement of these abnormalities. Conclusions The clinical co-occurrence of depressive episodes and presentation of AIWS can be interpreted to mean that they have certain functional disturbances in common. In view of incapacity, indifference, devitalization, altered perception of one’s body image, and disturbed sense of time and space, the features of AIWS analogous to those of psychotic depression imply a common psychopathological basis. These high-order brain dysfunctions are possibly associated with the metabolic abnormalities in visual and parietotemporal association cortices that we observed on the pre- and post-treatment FDG-PET images in this case, while the hypometabolism in the frontal cortex is probably associated with depressive symptoms.