Evaluation of a new point-of-care testing for creatinine and urea measurement

Anne-Sophie Bargnoux (1, 2) , Nils Kuster (1, 2) , Thibault Sutra (1, 2) , Laëtitia Laroche (2) , Annie Rodriguez (2) , Marion Morena (1, 2) , Leila Chenine (2) , Lotfi Chalabi (2) , Anne-Marie Dupuy (2, 3) , Stéphanie Badiou (1, 2) , Jean-Paul Cristol (1, 2)

1 PhyMedExp - Physiologie & médecine expérimentale du Cœur et des Muscles [U 1046]
2 CHRU Montpellier - Centre Hospitalier Régional Universitaire [Montpellier]
3 INM - Institut des Neurosciences de Montpellier

Point of care testing makes it possible to obtain results in an extremely short time. Recently, radiometer has expanded the panel of tests available on its ABL90 FLEX PLUS blood gas analyzer (ABL90) by adding urea and creatinine. The aim of this study was to verify the performance of these new parameters. This included assessment of imprecision, linearity, accuracy by comparison with central laboratory standard assays and interferences. In addition, clinical utility in a dialysis center was evaluated. Within-lab coefficients of variation were close to 2%. The mean and limits of agreement (mean ± 1.96 SD) of the difference between ABL90 and Roche enzymatic assays on cobas 8000 were 0.5 (from -1.4 to 2.3) mmol/L and -0.9 (from -19.5 to 17.8) µmol/L for urea and creatinine, respectively. The ABL90 enzymatic urea and creatinine assays met the acceptance criteria based on biological variation for imprecision and showed good agreement with central laboratory. The two assays were unaffected by hematocrit variation between 20 and 70%, hemolysis and icterus interferences. It should be noted that the relationship between lab methods and ABL90 was conserved even for high pre-dialysis values allowing easy access to dialysis adequacy parameters (Kt/V) and muscle mass evaluation (creatinine index). Rapid measurement of creatinine and urea using whole blood specimens on ABL90 appears as a fast and convenient method. Analytical performances were in accordance with our expectations without any significant interferences by hemolysis or icterus.

Mots clés: Creatinine; Analytical performances; Interferences; Point-of-care testing; Urea

Domaines: Sciences du Vivant [q-bio]; Médecine humaine et pathologie

Anne-Sophie Bargnoux, Nils Kuster, Thibault Sutra, Laëtitia Laroche, Annie Rodriguez, et al.. Evaluation of a new point-of-care testing for creatinine and urea measurement. Scandinavian Journal of Clinical and Laboratory Investigation, In press, 81 (4), pp.280-297. ⟨10.1080/00365513.2021.1914344⟩. ⟨hal-03211936⟩