Study of Cerebrospinal Fluid Tissue Transglutaminase , T - TAU , Amyloid Β 42 in Alzheimer ’ s Disease

Biochemical markers for Alzheimer disease would be of great value, especially to help in early diagnosis of the disease. The current study has focused on three candidates that have been suggested to be indulged in the pathogenesis of Alzheimer’ disease (AD): Tissue transglutaminase (tTG) activity, β-amyloid42 (Aβ 42) and total T-tau (T-tau). The study included 15 patients with probable AD, 15 patients with probable vascular dementia (VaD) in addition to 10 control subjects without neuropsychiatric diseases. The results of this study revealed that the CSF levels of total T-tau and activity of tTG, were significantly higher in patients with AD when compared with VaD and control. Also, CSF Aβ42 of patients with Alzheimer’s disease were significantly low when compared with vascular dementia, and controls. The sensitivity and specificity of CSF T-tau and Aβ42 were found to be high for differentiation of AD patients from controls, but their specificity against (VaD) is moderate. So, measurement of CSF tTG, T-tau and Aβ42 level in AD patients may provide useful and relatively simple biochemical tests for differentiating Alzheimer’s Disease from vascular dementia .In addition, the diagnostic usefulness of the CSF content of both T-tau and Aβ42 is superior to either measure alone with high sensitivity and specificity for prediction of AD, and can be recommended as an aid to evaluate individuals suspected of having dementia. (Egypt J. Neurol. Psychiat. Neurosurg., 2006, 43(2): 321-330)