Comparative Evaluation of PCT Measurement Using Three Different Chemiluminescence Methods

Procalcitonin (PCT) is now being recognized as a useful tool for monitoring infection and inflammation. Several vendors provide PCT measurement approaches using different detection reagents. In this analysis we compared Snibe MAGLUMI PCT, Beckman Dxi PCT and Roche Elecsys BRAHMS PCT, the latter being the method used to define the clinical decision cutoff points. We compared the analytical performance and the correlation between the different kits. Procalcitonin was evaluated in 122 samples by using MAGLUMI PCT assay (SNIBE), Elecsys BRAHMS PCT assay (Roche), and Dxi PCT assay (Beckman). We collected the samples from patients in the Intensive Care Unit (ICU) of the University Hospital of Heraklion. The linearity as well as the method of measurement were compared. The effect of Freezing and thawing was also evaluated. The data were analyzed using Passing-Bablok regression on MedCalc software. Additionally, we also evaluated the positive-negative agreement between samples. The results showed that one cycle of freezing and thawing did not have any effect in the PCT values obtained. There was a very good correlation between all three assays, with the strongest correlation being between Elecsys BRAHMS PCT and MAGLUMI PCT assays. Correlations between the different clinical cutoff points were provided showing that the closest correlation was between MAGLUMI PCT and Elecsys BRAHMS PCT.