This is a case report of an atypical presentation of early onset Alzheimer disease (EOAD) in a young patient with Capgras syndrome and cognitive impairment. The concurrent onset of psychiatric and cognitive symptoms prompted a detailed evaluation for a neurodegenerative disease. A 50-year-old male lawyer presented with low mood, apathy, delusions, and auditory hallucinations over 18 months. He considered his wife as an imposter and would require her text message to confirm her identity. He became more forgetful and had to give up his law practice. His neuropsychological assessment was impaired in all domains. Genetic testing revealed homozygosity for APOEe4 alleles. His magnetic resonance imaging showed predominant parietal and medial temporal atrophy, [18F]Fluorodeoxyglucose positron emission tomography showed frontal, parietal and posterior temporal hypometabolism and [18F]Flutemetamol positron emission tomography was positive for amyloid deposition, leading to the diagnosis of EOAD. This case highlights EOAD as a differential diagnosis in young patients who present with Capgras syndrome.

中文翻译：

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年轻的卡普格拉斯综合症：精神分裂症或阿尔茨海默氏病？

这是一例在卡普格拉斯综合症和认知功能障碍的年轻患者中非典型表现的早发性早老性阿尔茨海默病（EOAD）的病例报告。精神和认知症状的同时发作促使对神经退行性疾病进行详细评估。一名50岁的男性律师在18个月内表现出情绪低落，冷漠，妄想和幻听。他认为他的妻子是冒名顶替者，因此会要求她发送短信以确认其身份。他变得更加健忘，不得不放弃律师执业。他的神经心理学评估在所有领域均受损。遗传测试揭示了APOEe4等位基因的纯合性。他的磁共振成像显示主要的顶叶和内侧颞萎缩，[18F]氟去氧葡萄糖正电子发射断层扫描显示额叶，顶叶和后颞叶低代谢和[18F]氟美他莫正电子发射断层扫描对淀粉样蛋白沉积呈阳性，从而导致EOAD的诊断。该病例突出了EOAD作为卡普格拉斯综合症年轻患者的鉴别诊断。