Yoshita M, Taki J, Yokoyama K, Noguchi-Shinohara M, Matsumoto Y, Nakajima K, Yamada M
Department of Neurology and Neurobiology of Aging, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
Neurology. 2006 Jun 27;66(12):1850-4. doi: 10.1212/01.wnl.0000219640.59984.a7.
To evaluate the diagnostic reliability of cardiac iodine-123 metaiodobenzylguanidine ((123)I-MIBG) radioactivity in discriminating dementia with Lewy bodies (DLB) from Alzheimer disease (AD) regardless of parkinsonism.
The diagnosis of DLB may be confounded by the absence of parkinsonism. This highlights the need to improve the accuracy of antemortem diagnosis of DLB without parkinsonism.
Cardiac sympathetic denervation was examined using myocardial (123)I-MIBG scintigraphy in 37 patients with DLB, 42 patients with AD, and 10 normal elderly controls. The DLB patients consisted of seven patients without parkinsonism (DLB/P-) and 30 patients with parkinsonism (DLB/P+) at the time of the study.
The heart-to-mediastinum uptake ratio (H/M ratio) of myocardial MIBG uptake was decreased in both the DLB groups vs the AD group (p < 0.0001) and control group (p < 0.0001). The washout rate (WR) was higher in the DLB group than in the control group (p < 0.0001) and AD group (p < 0.0001). No differences were found between the AD and control groups or between the DLB/P+ and DLB/P- groups in either the early or delayed H/M ratio or WR. In discriminating between DLB and AD, regardless of parkinsonism, the delayed H/M ratio had a sensitivity of 100%, a specificity of 100%, and a positive predictive value of 100% at a cutoff value of 1.68.
Our results indicate that dementia with Lewy bodies results in cardiac sympathetic denervation and that iodine-123 metaiodobenzylguanidine myocardial scintigraphy is a sensitive tool for discriminating dementia with Lewy bodies from Alzheimer disease even in patients without parkinsonism.
评估心脏碘-123间碘苄胍（(123)I-MIBG）放射性在鉴别路易体痴呆（DLB）与阿尔茨海默病（AD）（无论是否存在帕金森综合征）方面的诊断可靠性。
DLB的诊断可能因无帕金森综合征而混淆。这凸显了提高无帕金森综合征的DLB生前诊断准确性的必要性。
对37例DLB患者、42例AD患者和10名正常老年对照者进行心肌(123)I-MIBG闪烁显像检查心脏交感神经去神经支配情况。DLB患者在研究时包括7例无帕金森综合征（DLB/P-）患者和30例有帕金森综合征（DLB/P+）患者。
与AD组（p < 0.0001）和对照组（p < 0.0001）相比，两个DLB组的心肌MIBG摄取的心脏与纵隔摄取比值（H/M比值）均降低。DLB组的洗脱率（WR）高于对照组（p < 0.0001）和AD组（p < 0.0001）。AD组与对照组之间或DLB/P+组与DLB/P-组之间在早期或延迟H/M比值或WR方面均未发现差异。在鉴别DLB和AD时，无论是否存在帕金森综合征，延迟H/M比值在临界值为1.68时，敏感性为100%，特异性为100%，阳性预测值为100%。
我们的结果表明，路易体痴呆会导致心脏交感神经去神经支配，并且碘-123间碘苄胍心肌闪烁显像即使在无帕金森综合征的患者中也是鉴别路易体痴呆与阿尔茨海默病的敏感工具。
