Evaluation of agreement between point-of-care and laboratory automated immunoassay in procalcitonin measurement among critically ill patients

Introduction: Procalcitonin (PCT) has attracted significant attention as a novel biomarker of sepsis. This study aimed to assess the agreement between blood results of PCT, obtained using the FinecareTM FIA Meter Plus (FS113), a point of-care (POC) procalcitonin testing device, and the automated Elecsys & REG; BRAHMS PCT assay on the Cobas e411, among critically ill septic patients.Methodology: This observational study was conducted in the intensive care unit of Hospital Universiti Sains Malaysia, in 2021. Whole blood samples were collected and tested with the FinecareTM FIA Meter Plus (FS113) (Wondfo, China) for PCT measurement. Additionally, the same whole blood samples were centrifuged to produce plasma samples, which were then analyzed using the automated Elecsys & REG; BRAHMS PCT assay on the Cobas e411 (Roche Diagnostics, Germany).Results: A total of 40 samples were analyzed in this study. Both PCT measurement techniques demonstrated a significant correlation, with a correlation coefficient of 0.96. Regression analysis revealed the following results: an Ordinary Least Square (OLS) slope of 0.91 (95% CI 0.83, 1.00) with an intercept of 1.27 (95% CI-0.75, 3.29); a Deming slope of 0.95 (95% CI 0.80, 1.10) with an intercept of 0.77 (95% CI-0.44, 1.85); and a Passing-Bablok slope of 1.16 (95% CI 0.99, 1.36) with an intercept of 0.22 (95% CI 0.08, 0.58).Conclusion: The point-of-care procalcitonin measurement provided by the FinecareTM FIA Meter Plus presents a viable alternative for assessing procalcitonin levels among septic patients in the intensive care unit (ICU).