The Diagnostic Value Of Csf Amyloid-Beta(43) In Differentiation Of Dementia Syndromes

Amyloid-beta (A beta) is known as the most prominent core protein in Alzheimer's Disease (AD) senile plaques. Although research has focused mainly on A beta(40) and A beta(42) as potential cerebrospinal fluid (CSF) biomarkers, a range of A beta peptides with variable lengths has been demonstrated in the brains and CSF of AD patients. Recently, it has been found that the A beta(43) peptide may be more abundant than previously assumed, could therefore play an important role in AD pathophysiology, and hence also function as putative biomarker. In this study the value of CSF A beta(43) in AD diagnosis was investigated. A beta(43) levels in CSF were highly correlated with A beta(42) levels. Furthermore, in differentiation of AD from non-demented controls and from patients with Lewy body dementia and frontotemporal dementia, A beta(43) had an equal diagnostic value as A beta(42), both as a single biomarker and in combination with total and phosphorylated tau. In conclusion, quantification of A beta(43) in CSF does not add novel diagnostic information to the differential diagnosis of AD compared to existing biomarkers.