Stato dell’arte dell’immunodosaggio dei peptidi natriuretici di tipo B
1Fondazione Toscana G. Monasterio, Pisa
2Dipartimento di Ricerca Traslazionale, Università di Pisa
3Scuola Superiore Sant’Anna, Pisa
4Istituto di Fisiologia Clinica del CNR e QualiMedLab srl, Pisa
State of the art of B-type natriuretic peptide (BNP) immunoassays
Recent studies have demonstrated that the precursor of BNP (proBNP) constitutes the major part of BNP-related peptides detectable in plasma of patients with heart failure by the commercially available immunoassays considered specific for the BNP hormone. Since proBNP significantly cross-reacts with commercial immunoassays for BNP, manufacturers should test and clearly declare the cross-reaction with proBNP in their BNP methods. Owing to the differences in cross-reaction with proBNP as well as in specificity, respectively, for the NH2- or COOH-terminal part of the peptide hormone chain, BNP immunoassays show significant between-method differences. Immunoassays for NT-proBNP, which all use standard materials and antibodies provided by the same company, show lower differences (generally minore del 20%). Clinicians should take into account these differences among methods when they compare results obtained from different laboratories, which use different BNP immunoassays. Accordingly, the use of a common decisional limit for all BNP immunoassay methods, as suggested by the most recent international guidelines, may be unreliable.