Jump to ContentJump to Main Navigation

Clinical Chemistry and Laboratory Medicine (CCLM)

Published in Association with the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM)

Editor-in-Chief: Plebani, Mario

Editorial Board Member: Gillery, Philippe / Kazmierczak, Steven / Lackner, Karl J. / Lippi, Giuseppe / Melichar, Bohuslav / Schlattmann, Peter / Whitfield, John B.

12 Issues per year

IMPACT FACTOR 2013: 2.955
Rank 5 out of 29 in category Medical Laboratory Technology in the 2013 Thomson Reuters Journal Citation Report/Science Edition

VolumeIssuePage

Issues

Variability in longitudinal cerebrospinal fluid tau and phosphorylated tau measurements

Nicolaas A. Verwey1 / Femke H. Bouwman2 / Wiesje M. van der Flier3 / Rob Veerhuis4 / Philip Scheltens5 / Marinus A. Blankenstein6

1Neurology Department, VU University Medical Center, Alzheimer Center, Amsterdam, The Netherlands and Clinical Chemistry Department, VU University Medical Center, Alzheimer Center, Amsterdam, The Netherlands

2Neurology Department, VU University Medical Center, Alzheimer Center, Amsterdam, The Netherlands

3Neurology Department, VU University Medical Center, Alzheimer Center, Amsterdam, The Netherlands

4Clinical Chemistry Department, VU University Medical Center, Alzheimer Center, Amsterdam, The Netherlands

5Neurology Department, VU University Medical Center, Alzheimer Center, Amsterdam, The Netherlands

6Clinical Chemistry Department, VU University Medical Center, Alzheimer Center, Amsterdam, The Netherlands

Corresponding author: N.A. Verwey, MD, Department Clinical Chemistry, VU University Medical Center, P.O. Box 7057, 1007, Amsterdam, The Netherlands Phone: +31-204443868,

Citation Information: Clinical Chemistry and Laboratory Medicine. Volume 46, Issue 9, Pages 1300–1304, ISSN (Online) 1437-4331, ISSN (Print) 1434-6621, DOI: 10.1515/CCLM.2008.241, July 2008

Publication History

Received:
2008-02-12
Accepted:
2008-04-21
Published Online:
2008-07-07

Abstract

Background: The influence of assay variation and duration of storage on changes in cerebrospinal fluid (CSF) levels of tau and phosphorylated (P)-tau with time was evaluated in 112 patients with various neurological disorders.

Methods: These patients (aged 66±9 years, 52% male), referred to our memory clinic, underwent two spinal taps (mean interval 19 months) and the baseline samples were assayed twice in a sandwich enzyme-linked immunosorbent assay (ELISA): once after the first spinal tap (A1) and once in a separately stored aliquot (A2) simultaneous with the follow-up sample (B).

Results: Coefficients of variances (CVs) of tau and P-tau levels determined in repeated spinal taps (ΔB–A2) measured in one assay (10.9% and 7.6%) were lower (p<0.01) than the CVs observed in two different (ΔB–A1) assays (16.5% and 11.7%). The CVs of tau and P-tau measurement of one CSF sample repeated on two occasions (ΔA1–A2) were 12.3% and 8.6%. A difference in mean P-tau level was found if the same CSF samples were repeatedly measured in two different ELISAs (A1–A2).

Conclusions: Longitudinal CSF tau and P-tau are best measured in one assay resulting in a lower variability compared to measurement in two different assays. The within person variability in levels of these markers currently limits the use of these ELISAs in a longitudinal clinical setting.

Clin Chem Lab Med 2008;46:1300–4.

Keywords: Alzheimer's disease; biomarker; cerebrospinal fluid; phosphorylated (P)-tau; tau

Comments (0)

Please log in or register to comment.
Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.