A Comparison Study: Possible Bias in Troponin I Measurement Obtained with a Point of Care Testing and a Central Laboratory Analyzers Employing Different Biological Matrices and Anticoagulants

Antonino Sammartano; Ruggero Buonocore; Roberto Fiorini; Elisabetta Dieci; Anna Di Franco; Bruna Di Stasi; Giovanni Tortorella; Luigi Ippolito

doi:10.3390/diagnostics14141482

A Comparison Study: Possible Bias in Troponin I Measurement Obtained with a Point of Care Testing and a Central Laboratory Analyzers Employing Different Biological Matrices and Anticoagulants

Diagnostics (Basel). 2024 Jul 10;14(14):1482. doi: 10.3390/diagnostics14141482.

Authors

Antonino Sammartano¹, Ruggero Buonocore², Roberto Fiorini³, Elisabetta Dieci², Anna Di Franco², Bruna Di Stasi², Giovanni Tortorella⁴, Luigi Ippolito¹

Affiliations

¹ U.O. Clinical Pathology, Medical and Diagnostics Department P.O. Fidenza, Azienda AUSL of Parma, 43125 Parma, Italy.
² U.O. Biochemical, Department of Clinical Patology, Ospedale Guglielmo da Saliceto of Piacenza, 29121 Piacenza, Italy.
³ Emergency Department, Vaio Hospital, Azienda AUSL of Parma, 43125 Parma, Italy.
⁴ Cardiology Unit, Medical and Diagnostics Department P.O. Fidenza, Azienda AUSL of Parma, 43125 Parma, Italy.

Abstract

Background: high-sensitive cardiac TroponinI (hs-cTnI) is widely used for diagnosis of acute coronary syndromes. The latest recommendation for hs-cTnI determination is the protocol 0-1 h finalized to improve the rule out accuracy of the test. A Point of Care Testing able to guarantee these performances could be very useful due to reducing the turnaround time and ruling out patients suspected of ACS, especially by using biological matrices that are not required for centrifuge. The aim of our work is to compare the results for hs-cTnI obtained using different biological matrices and anticoagulants, obtained between Atellica^® VTLi hs-cTnI POCT and Access AccuTnI+3 DxI800 performances, in order to establish a possible bias derived directly from these pre-analytical conditions.

Methods: Li-heparinized pool samples were primary employ for hs-cTnI with Atellica^® VTLi as whole blood, then centrifuged and tested on Atellica^® VTLi and DxI800. K₃EDTA pool samples were centrifuged and measured on DxI800 too. A comparison of methods was performed according to CLSI_EP-09A2 protocol. Constant and proportional errors were investigated with Deming regression. Bias between methods was evaluated with the Bland Altman test.

Results: comparing whole blood lithium heparin results obtained with Atellica versus lithium heparin and K₃EDTA plasma tested on DxI 800, the Deming regression revealed a proportional error, whereas in both cases Bland Altman highlighted a minimal underestimation. A similar performance was revealed when considering plasma lithium heparin tested on Atellica versus lithium heparin and K₃EDTA plasma obtained with DxI800, confirming the same underestimation. Considering values close to the cut off, no significant differences were found.

Conclusions: in the laboratory, the estimation of the bias of two different analyzers is pivotal. Once more this is crucial when different biological matrices and anticoagulants are employed for the analysis. Our study demonstrates that no significant differences among the two matrices are present when comparing Atellica and DxI800 performances.

Keywords: high-sensitivity; myocardial injury; point of care; troponin.

Grants and funding

This research received no external funding.