Diagnostic biomarkers in Alzheimer's disease

In this review article we examine the various types of diagnostic biomarkers which are used in the early detection of Alzheimer's disease. This review summerizes the A/T/N classification system for Alzheimer's biomarkers and its use in the biomarker-based diagnosis of Alzheimer's disease. Furthermore we review the use of structural MRI, 18F-FDG PET, Amyloid PET, Tau PET, cerebrospinal fluid biomarkers, and the emerging role of plasma biomarkers in the diagnosis of Alzheimer's disease. In doing so we discuss each biomarkers correlation with pathologic findings, ability to distinguish Alzheimer's disease from healthy aging, ability to distinguish Alzheimer's disease from other neurodegenerative diseases, role in A/T/N classification system, and limitations of each biomarker.