脑脊液中β-淀粉样蛋白检测与阿尔茨海默病的早期诊断

目的：检测β—淀粉样蛋白(β—amyloid protein，Aβ)两种主要成分Aβl-40和Aβ1—42在阿尔茨海默病(Alzheier's Disease，AD)脑脊液中的变化，并探讨其对AD的诊断价值。方法：采用敏感的双抗体夹心酶联免疫吸附法(ELISA)，检测54例AD患脑脊液中Aβ的浓度，并与30例正常对照(normal controls，NC)脑脊液中的相应成分进行对比。结果：①AD患脑脊液中Aβ1—42浓度低于正常对照组，而Aβl-40／Aβl—42比值高于对照组；②以脑脊液中Aβ比值及Aβl—42浓度检测诊断AD的敏感性分别为54．51％、90．00％，特异性为84．25％、84．38％。结论：临床上同时检测脑脊液中Aβl—42浓度及Aβ比值可作为早期诊断AD的辅助指标，具有一定的临床应用价值。

The Value of CSF Level of β-amyloid Protein in the Diagnosis of Alzheimer's Disease

Objective:To evaluate the diagnostic potential of cerebrospinal fluid ( CSF) levels of β-amyloid protein (Aβ) as biochemical marker for senile dementia in clinical practice. Methods: Sensitive enzyme-linked immunosorbent assay ( ELISA) was performed in our laboratory to detect the CSF levels of Aβ1-40, Aβ1-42 in 54 patients with Alzheimer's disease (AD), and 30 normal controls (NC). Results: The cut off value of Aβ ratio and Aβ1-42 concentration in NC group provided 54. 51%, 90. 00% sensitivity and 81. 25%, 84. 38% specificity respectively in diagnosis of AD. Conclusion: AD group bad a significant decreased level of Aβ1-42 and an increased level of Aβ ratio, compared with NC group.