Diagnostic and prognostic utilities of multimarkers approach using procalcitonin, B-type natriuretic peptide, and neutrophil gelatinase-associated lipocalin in critically ill patients with suspected sepsis

Background: We investigated the diagnostic and prognostic utilities of procalcitonin (PCT), B-type natriuretic peptide (BNP), and neutrophil gelatinase-associated lipocalin (NGAL) in critically ill patients with suspected sepsis, for whom sepsis was diagnosed clinically or based on PCT concentrations. Methods: PCT, BNP, and NGAL concentrations were measured in 340 patients and were followed up in 109 patients. All studied biomarkers were analyzed according to the diagnosis, severity, and clinical outcomes of sepsis. Results: Clinical sepsis and PCT-based sepsis showed poor agreement (kappa = 0.2475). BNP and NGAL showed significant differences between the two groups of PCT-based sepsis (P = 0.0001 and P < 0.0001), although there was no difference between the two groups of clinical sepsis. BNP and NGAL were significantly different according to the PCT staging and sepsis-related organ failure assessment subscores (P < 0.0001, all). BNP and PCT concentrations were significantly higher in the non-survivors than in the survivors (P = 0.0002) and showed an equal ability to predict in-hospital mortality (P = 0.0001). In the survivors, the follow-up NGAL and PCT concentrations were significantly lower than the initial values (148.7 ng/mL vs. 214.5 ng/mL, P < 0.0001; 0.61 ng/mL vs. 5.56 ng/mL, P = 0.0012). Conclusions: PCT-based sepsis diagnosis seems to be more reliable and discriminating than clinical sepsis diagnosis. Multimarker approach using PCT, BNP, and NGAL would be useful for the diagnosis, staging, and prognosis prediction in the critically ill patients with suspected sepsis.