Accessible Requires Authentication Published by De Gruyter September 11, 2007

Intra-individual variation in creatinine and cystatin C

Niluka Bandaranayake, Thelma Ankrah-Tetteh, Sethsiri Wijeratne and Ramasamyiyer Swaminathan
From the journal


Background: Serum creatinine and cystatin C are measured in the assessment of glomerular filtration rate. Biological variation of an analyte is an important determinant of its usefulness. Intra-individual variation in serum creatinine and cystatin C in healthy subjects was determined in this study.

Methods: Weekly blood samples were taken from 10 healthy subjects and analysed for creatinine (kinetic Jaffe method) and for cystatin C (by nephelometry).

Results: Intra-individual variations for serum creatinine and cystatin C were 6.1% and 4.55%, respectively. Index of individuality values were similar for the analytes (0.35 for both).

Conclusion: Intra-individual variations for serum creatinine and cystatin C were similar in healthy subjects.

Clin Chem Lab Med 2007;45:1237–9.

Corresponding author: Prof. R. Swaminathan, Department of Chemical Pathology, St. Thomas' Hospital, 5th Floor, North Wing, Lambeth Palace Road, London SE1 7EH, UK Phone: +44-20-71881285 ext 3542, Fax: +44-20-79284226,

Received: 2007-3-26
Accepted: 2007-5-14
Published Online: 2007-09-11
Published in Print: 2007-09-01

©2007 by Walter de Gruyter Berlin New York