title: The clinical use of cerebrospinal fluid biomarker testing for Alzheimer's disease diagnosis: a consensus paper from the Alzheimer's Biomarkers Standardization Initiative.
abstract: BACKGROUND
  Cerebrospinal fluid (CSF) biomarkers β-amyloid 1-42 (Aβ1-42), also expressed as Aβ1-42:Aβ1-40 ratio, T-tau, and P-tau181P, have proven diagnostic accuracy for mild cognitive impairment and Alzheimer's disease (AD). How to use, interpret, and disclose biomarker results drives the need for standardization.
  
  
  METHODS
  Previous Alzheimer's Biomarkers Standardization Initiative meetings discussed preanalytical issues affecting Aβ1-42 and tau in CSF. This second round of consensus meetings focused on issues related to clinical use of AD CSF biomarkers.
  
  
  RESULTS
  Consensus was reached that lumbar puncture for AD CSF biomarker analysis be considered as a routine clinical test in patients with early-onset dementia, at the prodromal stage or with atypical AD. Moreover, consensus was reached on which biomarkers to use, how results should be interpreted, and potential confounding factors.
  
  
  CONCLUSIONS
  Changes in Aβ1-42, T-tau, and P-tau181P allow diagnosis of AD in its prodromal stage. Conversely, having all three biomarkers in the normal range rules out AD. Intermediate conditions require further patient follow-up.
authors.affiliation: Alzheimer's Disease and Other Cognitive Disorders Unit, Hospital Clinic i Universitari, IDIBAPS and Barcelona Beta Research Centre, Pasqual Maragall Foundation, Barcelona, Spain. Electronic address: JLMOLI@clinic.ub.es.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Molinuevo
authors.affiliation: Clinical Neurochemistry Laboratory, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.
authors.forename: Kaj
authors.initials: K
authors.lastname: Blennow
authors.affiliation: Centre des Maladies Cognitives et Comportementales, Hôpital de la Salpêtrière, AP-HP, Institute of Brain and Spinal Cord (ICM), UMR-S975, Université Pierre et Marie Curie-Paris 6, Paris, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Dubois
authors.affiliation: Department of Neurology and Memory Clinic, Hospital Network Antwerp (ZNA), Middelheim and Hoge Beuken, Antwerp, Belgium; Reference Centre for Biological Markers of Dementia (BIODEM), Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.
authors.forename: Sebastiaan
authors.initials: S
authors.lastname: Engelborghs
authors.affiliation: Department of Psychiatry and Psychotherapy, Universitätsklinikum Erlangen and Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany.
authors.forename: Piotr
authors.initials: P
authors.lastname: Lewczuk
authors.affiliation: Centre for Memory Resources and Research (CMRR), Neurobiology Laboratory, GHE, Hôpitaux de Lyon, Université Lyon 1, CNRS UMR5292, INSERM U1028, Lyon, France.
authors.forename: Armand
authors.initials: A
authors.lastname: Perret-Liaudet
authors.affiliation: Neurochemistry Laboratory and Biobank, Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Charlotte E
authors.initials: CE
authors.lastname: Teunissen
authors.affiliation: Centre for Memory Disturbances and Alzheimer's Centre, Section of Neurology, University of Perugia, Perugia, Italy.
authors.forename: Lucilla
authors.initials: L
authors.lastname: Parnetti
mesh_terms: D000544:Alzheimer Disease / Q000134:cerebrospinal fluid* / Q000175:diagnosis*; D016229:Amyloid beta-Peptides / Q000134:cerebrospinal fluid; D015415:Biomarkers / Q000134:cerebrospinal fluid*; D060825:Cognitive Dysfunction / Q000134:cerebrospinal fluid / Q000175:diagnosis; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D010446:Peptide Fragments / Q000134:cerebrospinal fluid; D012015:Reference Standards; D016875:tau Proteins / Q000134:cerebrospinal fluid
chemical_list: D016229:Amyloid beta-Peptides; D015415:Biomarkers; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40); C075222:amyloid beta-protein (1-42); D016875:tau Proteins
keywords: Alzheimer's disease; Amyloid-β peptides; Biomarkers; Cerebrospinal fluid; Standardization; Tau