特異な妄想性人物誤認を呈した1例

A Case of a Special Form of Delusional Misidentification

　【抄録】うつ病から双極性障害，さらに精神分裂病という診断の変遷をたどり，てんかん発作も出現するという非定型な経過の中で，特異な妄想性人間誤認症状を呈した，22歳の女性の症例を報告した。この人物誤認は，人物に対する些細な類似点について，何らかの家族関係があるという妄想意味を付与する妄想知覚であり，妄想体系に組み込まれず断片的で，自分と関係のない家族関係にもみられた。その他の特異な精神症状（同一人物の同定の失敗，持ち物や声の否認），てんかん発作および右半球焦点のspike ＆ waveがみられたこと，反響言語，記銘力障害などの脳の器質的障害を疑わせる臨床所見などから，何らかの神経心理学的認知障害が関連している可能性も疑われた。

　We described a 22-year-old woman who had previously been diagnosed as having major depression, bipolar disorder, schizophrenia, and epilepsy. She had a unique kind of interpretation delusion. She believed that any person, who had some resemblance to a member of her family, was a member of her family. For example, “that nurse is my sister, because her face looks like me” and “Dr. A is my brother, because I feel comfortable talking with him.” Her delusion was occasional and was not systematic. She also had other misidentification syndromes, such as MacCallum syndrome, neglect of her own belongings, and neglect of her own and other persons'voice. She had had an epileptic focus in the right parietooccipital region. She also had echolalia, delayed echolalia, disturbance of shortterm memory, and slight motor impersistence. This unique form of delusional misidentification, named “misidentification of relationship”, may be caused by synergism of psychodynamics and some neuropsychological deficit.