Abstract:

Objective To assess the accuracy and consistency of point-of-care testing （POCT） technology in detecting D-dimer （DDI）， Procalcitonin （PCT）， and N-terminal pro B-type natriuretic peptide （NT-proBNP） in whole blood samples， as well as to validate its feasibility for rapid clinical diagnosis. Methods From July 8 to August 22， 2022， a total of 104 paired DDI whole blood and plasma samples， 496 paired PCT whole blood and serum samples， and 77 paired NT-proBNP whole blood and serum samples were collected. The consistency and accuracy of test results between whole blood and plasma/serum samples were assessed using the Mann-Whitney U test， regression analysis， relative sensitivity， relative specificity， Youden′s index， and Kappa value. Results The test results of DDI， PCT， and NT-proBNP in whole blood and plasma/serum samples demonstrated excellent consistency， with correlation coefficients of r2 = 0.951 2， r2 = 0.942 8， and r2 = 0.991 6， respectively， and all P-values exceeding 0.05. At the medical decision levels， for DDI （0.55 μg/mL）， the relative sensitivity， relative specificity， Youden index， and Kappa value were 94.3%， 94.1%， 0.88， and 0.87， respectively. For PCT （0.5 ng/mL and 2.0 ng/mL）， the relative sensitivities were 97.4% and 89.0%， the relative specificities were 95.8% and 98.3%， the Youden indices were 0.93 and 0.87， and the Kappa values were 0.93 and 0.89， respectively. For NT-proBNP （125 pg/mL）， the relative sensitivity was 94.1%， the relative specificity was 100%， the Youden index was 0.94， and the Kappa value was 0.87. These findings confirm the high accuracy of whole blood sample testing and the strong concordance between the two methods. Conclusions This study confirmed the efficacy of POCT technology for detecting DDI， PCT， and NT-proBNP in whole blood samples. The results showed a high level of consistency compared to traditional plasma/serum methods， thereby reinforcing the clinical applicability of POCT for rapid diagnosis.

Key words: point-of-care testing, D-dimer, procalcitonin, N-terminal pro B-type natriuretic peptide, whole blood samples, plasma/serum samples