Differential diagnosis of dementing diseases
Differential diagnosis of dementing diseases
复制标题
痴呆性疾病的鉴别诊断
作者：
L. Barclay
对认知受损患者的评估需要在标准和强大的神经心理学测试的帮助下记录痴呆，然后识别局灶性、多灶性或皮质下神经系统体征，这些体征有助于区分最常见的痴呆疾病。通常的诊断难题是区分阿尔茨海默病和循环性痴呆。直到最近，阿尔茨海默病还被认为是一种排除性诊断，只能通过病理检查来确认。侵入性测试，如腰椎穿刺蛋白质标记或皮肤活检遗传标记，可能有助于阿尔茨海默氏症的生前诊断。可以提供诊断线索的非侵入性确定的信息包括痴呆症家族史和指纹图案。循环性痴呆不必局限于多发梗塞性痴呆，还可以包括伴随脑血管或心血管疾病的痴呆。与循环性痴呆相关的特征包括泌尿和步态障碍的遥远病史、耳毛生长以及MRI和CTT上的"梗死"。虽然MRI上的"梗死"的意义尚不清楚，但它们与高Hachinski缺血评分、高血压和心律失常有关。在诊断循环性痴呆时，MRI上的"梗塞"比CTT上的"梗塞"更敏感，但特异性较低。决策分析技术可以帮助确定Hachinski评分及其组成部分的诊断效用，以及成像技术和其他诊断辅助工具在鉴别诊断中的应用。在阿尔茨海默氏症的药物试验中，需要最大限度地提高诊断循环性痴呆的灵敏度，以排除不合适的受试者，MRI是首选的成像程序。相反，循环性痴呆的药物试验应该使用CTT来提高特异性。在没有特定治疗干预的情况下，可以使用任何一种程序，因为CTT和MRI的总体诊断效用（由Brier评分确定）相当。
Evaluation of the cognitively impaired patient necessitates documentation of dementia, with the help of standard and robust neuropsychological tests, followed by identification of focal, multifocal, or subcortical neurological signs which help differentiate the most common dementing diseases. The usual diagnostic dilemma is to distinguish Alzheimer’s disease from circulatory dementia. Until recently, Alzheimer’s disease was considered a diagnosis of exclusion, with confirmation only by pathological examination. Invasive tests, such as lumbar puncture for protein markers or skin biopsy for genetic markers, may aid in the antemortem diagnosis of Alzheimer’s. Noninvasively determined information which may provide diagnostic clues includes family history of dementia and fingerprint patterns. Circulatory dementia need not be confined to multi-infarct dementia, but may also include dementia accompanying cerebrovascular or cardiovascular disease. Features associated with circulatory dementia include remote history of urinary and gait disturbances, ear hair growth, and “infarcts” on MRI and CTT. Although the significance of “infarcts” on MRI is unclear, they are associated with high Hachinski ischemic score, hypertension, and cardiac arrhythmias. “Infarcts” on MRI are more sensitive, but less specific, than “infarcts” on CTT, in diagnosing circulatory dementia. Techniques of decision analysis can help determine the diagnostic utility of the Hachinski score and its components, as well as of imaging techniques and other diagnostic aids, in differential diagnosis. In drug trials for Alzheimer’s, where maximum sensitivity in the diagnosis of circulatory dementia is needed to exclude inappropriate subjects, the MRI is the imaging procedure of choice. Conversely, drug trials for circulatory dementia should use the CTT to enhance specificity. In the absence of specific therapeutic intervention, either procedure may be used, as overall diagnostic utility of the CTT and MRI, as determined by the Brier score, is comparable.