Abstract
Background Differential diagnosis of neurodegenerative dementia is currently supported by biomarkers including cerebrospinal fluid (CSF) tests. Among them, CSF total-tau (t-tau), phosphorylated tau (p-tau) and β-amyloid42 (Aβ42) are considered core biomarkers of neurodegeneration. In the present work, we hypothesize that simultaneous assessment of these biomarkers together with CSF α-synuclein (α-syn) will significantly improve the differential diagnostic of Alzheimer’s disease and other dementias. To that aim, we characterized the analytical and clinical performance of a new tetra-plex immunoassay that simultaneously quantifies CSF Aβ42, t-tau, p-tau and α-syn in the differential diagnosis of neurodegenerative dementia. Methods Biomarkers’ concentrations were measured in neurological controls (n=38), Alzheimer’s disease (n=35), Creutzfeldt-Jakob disease (n=37), vascular dementia (n=28), dementia with Lewy bodies/Parkinson’s disease dementia (n=27) and frontotemporal dementia (n=34) using the new tetra-plex assay and established single-plex assays. Biomarker’s performance was evaluated and diagnostic accuracy in the discrimination of diagnostic groups was determined using partial least squares discriminant analysis. Results The tetra-plex assay presented accuracies similar to individual single-plex assays with acceptable analytical performance. Significant correlations were observed between tetra-plex and single-plex assays. Using partial least squares discriminant analysis, Alzheimer’s disease and Creutzfeldt-Jakob disease were well-differentiated, reaching high accuracies in the discrimination from the rest of diagnostic groups. Conclusions The new tetra-plex assay coupled with multivariate analytical approaches becomes a valuable asset for the differential diagnosis of neurodegenerative dementia and related applications.
Characterization and clinical use of inflammatory cerebrospinal fluid protein markers in Alzheimer’s disease
