Rubí S, Noguera A, Tarongí S, Oporto M, García A, Vico H, Espino A, Picado M J, Mas A, Peña C, Amer G
Servicio de Medicina Nuclear, Hospital Universitari Son Espases, Palma, España; Instituto de Investigación Sanitaria de Palma (IdISPa), Palma, España.
Servicio de Análisis Clínicos, Hospital Universitari Son Espases, Palma, España.
Rev Esp Med Nucl Imagen Mol (Engl Ed). 2018 Jan-Feb;37(1):3-8. doi: 10.1016/j.remn.2017.05.003. Epub 2017 Jun 20.
Cortical posterior hypometabolism on PET imaging with F-FDG (FDG-PET), and altered levels of Aß peptide, total Tau (tTau) and phosphorylated Tau (pTau) proteins in cerebrospinal fluid (CSF) are established diagnostic biomarkers in Alzheimer's disease (AD). An evaluation has been made of the concordance and relationship between the results of FDG-PET and CSF biomarkers in symptomatic patients with suspected AD.
A retrospective review was carried out on 120 patients with cognitive impairment referred to our Cognitive Neurology Unit, and who were evaluated by brain FDG-PET and a lumbar puncture for CSF biomarkers. In order to calculate their Kappa coefficient of concordance, the result of the FDG-PET and the set of the three CSF biomarkers in each patient was classified as normal, inconclusive, or AD-compatible. The relationship between the results of both methods was further assessed using logistic regression analysis, including the Aß, tTau and pTau levels as quantitative predictors, and the FDG-PET result as the dependent variable.
The weighted Kappa coefficient between FDG-PET and CSF biomarkers was 0.46 (95% CI: 0.35-0.57). Logistic regression analysis showed that the Aß and tTau values together were capable of discriminating an FDG-PET result metabolically suggestive of AD from one non-suggestive of AD, with a 91% sensitivity and 93% specificity at the cut-off line Aß=44+1.3×tTau.
The level of concordance between FDG-PET and CSF biomarkers was moderate, indicating their complementary value in diagnosing AD. The Aß and tTau levels in CSF help to predict the patient FDG-PET cortical metabolic status.
采用氟代脱氧葡萄糖（F-FDG）进行PET成像时皮质后代谢减低，以及脑脊液（CSF）中β淀粉样蛋白（Aβ）、总tau蛋白（tTau）和磷酸化tau蛋白（pTau）水平改变是阿尔茨海默病（AD）已确立的诊断生物标志物。本研究对疑似AD的有症状患者的FDG-PET结果与CSF生物标志物结果之间的一致性和关系进行了评估。
对转诊至我院认知神经科的120例认知障碍患者进行回顾性研究，这些患者均接受了脑FDG-PET检查及腰椎穿刺以检测CSF生物标志物。为计算其Kappa一致性系数，将每位患者的FDG-PET结果和三种CSF生物标志物组合分类为正常、不确定或与AD相符。使用逻辑回归分析进一步评估两种方法结果之间的关系，将Aβ、tTau和pTau水平作为定量预测指标，将FDG-PET结果作为因变量。
FDG-PET与CSF生物标志物之间的加权Kappa系数为0.46（95%CI：0.35 - 0.57）。逻辑回归分析表明，Aβ和tTau值共同能够区分代谢上提示AD的FDG-PET结果与不提示AD的结果，在截断线Aβ = 44 + 1.3×tTau时，敏感性为91%，特异性为93%。
FDG-PET与CSF生物标志物之间的一致性水平为中等，表明它们在AD诊断中具有互补价值。CSF中的Aβ和tTau水平有助于预测患者的FDG-PET皮质代谢状态。
