Evaluation of the hemolysis threshold for the measurement of serum lipase on Roche Cobas systems

Abstract

Objectives: Following the release of an informational bulletin, Roche Diagnostics adopted a more restrictive hemolysis index (100 HI) for the release of serum lipase results on all Cobas systems. This study aimed to evaluate the interference threshold for serum lipase hemolysis on Cobas C501/311/701/Integra 400 systems using a total allowable error set by the Royal College of Pathologists of Australasia (RCPA). Methods: To assess the influence of hemolysis on lipase, the parameter was quantified in serum pools spiked with escalating concentrations of a hemolysis interferent. The lipase assay was performed using the colorimetric lipase method (LIPC), and the HI was determined by absorbance measurements of diluted samples in accordance with the system protocol. Results: The Cobas Integra 400 and Cobas C311 showed the greatest interference of lipase with hemolysis (≤300 HI). The Cobas C501 and C701 demonstrated less sensitivity to hemolysis (≤1300 HI). Conclusion: The results of this study demonstrate that interference limits may vary between different Roche systems, even when the same reagent is used. Our study indicated that the lipase hemolysis threshold (100 HI) currently set by the manufacturer was excessively restrictive. This finding highlights the necessity of verifying manufacturers' information bulletins to provide better medical care. Keywords: Hemolysis, interference, lipase, threshold