Extent of bilirubin interference with Beckman creatinine methods.
BACKGROUND
The aim of the study was to determine the extent of bilirubin interference on two different Beckman-Coulter creatinine methods used on the CX5 PRO/DxC 600 and the DxC 800 systems, respectively.


METHODS
The Beckman methods were compared with a high-performance liquid chromatography (HPLC) method using 104 patient samples with creatinine concentrations <133 micromol/L and bilirubin concentrations of between 30 and 802 micromol/L.


RESULTS
The linear regression analysis calculations expressing the relationship between bilirubin concentration and the observed difference between the Beckman and HPLC creatinine methods are: DxC800 creatinine M (modular or cup) method: r(2) 0.217, slope -0.023 and intercept 6.43; and DxC600 method: r(2) 0.7324, slope -0.0882 and intercept 12.01.


CONCLUSIONS
There is significantly greater interference by bilirubin on the CX5 PRO/DxC 600 method, which can lead to inaccuracy in the calculation of the estimated glomerular filtration rate by the Modification of Diet in Renal Disease equation.
Dimeski
Goce
G
Department of Chemical Pathology, Queensland Health Pathology Service (QHPS), Princess Alexandra Hospital, Ipswich Road, Woolloongabba, Queensland 4102, Australia. Goce_Dimeski@health.qld.gov.au
McWhinney
Brett
B
Jones
Brock
B
Mason
Rebecca
R
Carter
Andrew
A
D016477:Artifacts; D001663:Bilirubin / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003404:Creatinine / Q000097:blood*; D006801:Humans
D003404:Creatinine; D001663:Bilirubin