RESUMO
BACKGROUND: In this study, we compared the B.R.A.H.M.S Kryptor procalcitonin (PCT) assay with the newly developed ADVIA Centaur B.R.A.H.M-S PCT assay. Furthermore, the long-term stability of PCT at - 20 degrees C was assessed. METHODS: Samples from 97 patients with lower respiratory tract infections were retested on both systems and compared with Passing-Bablok regression over two clinically relevant cutoff ranges for PCT, 0 - 2.0 microg/L and > 2.0 microg/L. RESULTS: After storage for 2.5 to 4 years, PCT levels in patient sera declined only 3.7%. Passing-Bablok regression analysis of the total sample range (n = 97) showed that both methods correlated well (r = 0.9944), although with a deviation from the line of identity (y = 0.880x - 0.025 microg/L). Comparison of both methods within the clinically important interval of 0 - 2.0 microg/L showed acceptable correlation (y = 0.943x + 0.010 microg/L). CONCLUSIONS: The ADVIA Centaur B.R.A.H.M.S PCT assay showed good correlation with the established Kryptor method. Therefore, this new technique can be used in clinical routine with the same clinical interpretation.
