Latin American Experience with Alzheimer's Disease Cerebrospinal Fluid Biomarkers

Abstract

A promising advance to complement clinical diagnosis at an early stage of Alzheimer’s disease (AD) has been the measurement of biomarkers in cerebrospinal fluid (CSF).1 A decrease in CSF amyloid beta 42 (Ab42) is a marker of AD pathology caused by the accumulation of amyloid-b in brain parenchyma,2 whereas increased total tau (t-tau) and hyperphosphorylated tau (p-tau) reflect neuronal degeneration and tangle pathology.3 AD is characterized by episodic memory loss, cognitive impairment, behavioral disorders, and finally, dementia.4 Individuals with mild cognitive impairment (MCI) have memory defi- cits but, in contrast to those with AD, are functionally intact and at higher risk of converting to AD than those without MCI.4 It is difficult to predict clinically which individuals with MCI possess AD brain pathology and will therefore progress to clinical AD