[Near a biological diagnosis of Alzheimer's disease and related disorders].
OBJECTIVE
To review the current concepts in the biological diagnosis of Alzheimer's disease (AD) and related disorders.


BACKGROUND
As new therapeutics specific of AD may be available soon, early diagnosis of AD in the context of mild cognitive impairment (MCI) or dementia appears to be challenging. The high amount of atypical clinical forms of AD leads to develop new tools allowing in vivo diagnosis. New CerebroSpinal Fluid (CSF) biomarkers seem to reflect specific aspects of deep neuropathological changes observed in AD, i.e. amyloid deposits and neurofibrillary tangles. Amyloid beta-peptide 1-42 (Abeta(1-42)) and hyperphosphorylated tubulin associated unit (tau) isoforms appear to be the most sensitive and specific CSF biomarkers, the combination of these biomarkers depicting the best diagnosis value for AD. These molecules are also efficient in the prediction of the conversion from the MCI state to the dementia state of AD. Combined to clinical and neuro-imaging information, CSF biomarkers appear thus to be highly relevant in improving the early etiological diagnosis of dementia.


CONCLUSIONS
The current research focalises on the development of new molecules coming from Abeta and tau protein families, in the CSF and in the serum, as well as molecules reflecting other pathological metabolism changes, as alpha-synuclein in Lewy Body Disease. The diagnosis value of CSF biological markers is so promising that they have been recently included in the research diagnosis criteria of AD.
Krolak-Salmon
P
P
Service de médecine gériatrique, centre hospitalier Lyon-Sud, hospices civils de Lyon, Pierre-Bénite cedex, France. pierre.krolak-salmon@chu-lyon.fr
Seguin
J
J
Perret-Liaudet
A
A
Desestret
V
V
Vighetto
A
A
Bonnefoy
M
M
D000544:Alzheimer Disease / Q000134:cerebrospinal fluid / Q000175:diagnosis*; D016229:Amyloid beta-Peptides / Q000134:cerebrospinal fluid; D015415:Biomarkers / Q000134:cerebrospinal fluid; D001921:Brain / Q000473:pathology; D003952:Diagnostic Imaging; D006801:Humans; D051844:alpha-Synuclein / Q000134:cerebrospinal fluid; D016875:tau Proteins / Q000134:cerebrospinal fluid
D016229:Amyloid beta-Peptides; D015415:Biomarkers; C054369:MAPT protein, human; D051844:alpha-Synuclein; D016875:tau Proteins