LETTERS A Case of Late-Onset Bipolar Disorder With Severely Abnormal Behavior and Neuroimaging Observations Very Similar to Those of

(FTD) is mainly characterized by neuropsychiatric symptoms, usually preceding cognitive impairment, and an early impairment of executive functions, with relatively preserved memory and visuospatial skills.1 There have thus been some case reports of FTD that is initially diagnosed as schizophrenia or bipolar disorders (BP).2 We herein report a case of late-onset BP that was initially diagnosed as major depressive disorder and was temporarily diagnosed as FTD because of severely abnormal behaviors and neuroimaging observations that wer