脑脊液中β淀粉样蛋白检测对老年期痴呆的诊断意义

目的　研究阿尔茨海默病（AD）和血管性痴呆（VD）患者脑脊液(CSF)中β淀粉样蛋白（Aβ或βA

Detection of

Objective　To study the levels of β amyloid protein(Aβ/βA4) in cerebrospinal fluid(CSF) of patients with Alzheimer's disease(AD) and vascular dementia(VD) and its significance of diagnosis.Methods　The levels of Aβ1-40 and Aβ1-42 in CSF of 24 patients with AD, 14 patients with VD and 30 normal controls(NC) were detected by enzyme-linked immunosorbent assays(ELISA).Results　(1)The levels of Aβ1-42 in CSF of AD and VD patients were significantly lower than NC group (P<0.05). No difference in Aβ1-40 levels was observed among these groups;(2)The Aβ ratio (Aβ1-40/Aβ1-42) was constant in NC group (4.70±2.85), but the Aβ ratio in AD and VD patients was significantly higher than NC group (13.51±11.86, 12.69±7.41 respectively),the diffe-rence had significance (P<0.05);(3)If using the Aβ ratio 10.4 as the cut-off value, the sensitivity of senile dementia was 60.50%(23/38), and the specificity was 88.46%(23/26).Conclusion　AD and VD patients had significantly decreased level of Aβ1-42, and the ratio of Aβ1-40/Aβ1-42 was significantly higher than NC group. The Aβ ratio in CSF was provided in the diagnosis of senile dementia, it had higher specificity and sensibility in clinic.