Elimination of procalcitonin and plasma concentrations during continuous veno-venous haemodiafiltration in septic patients

The elimination of procalcitonin and the course of plasma concentrations during continuous venovenous haemodiafiltration were measured in patients with sepsis or multiple organ dysfunction syndrome, because these patients are a main target group for the measurement of procalcitonin and often require renal replacement therapy. Procalcitonin was measured in the prefilter plasma and the filtrate at 5 min, 15 min and 1, 2, 4, 6, 12, 24 h after set-up of continuous veno-venous haemodiafiltration. In a prospective study, 19 patients with plasma levels of procalcitonin >3 ng mL(-1) and acute oliguric renal failure treated with continuous veno-venous haemodiafiltration using a polysulphone membrane, were evaluated for the study of clearance. Twenty-one control patients (procalcitonin <2 ng mL(-1)) were studied to determine whether filtration itself induced a procalcitonin response. No interventions were required. In patients with low procalcitonin concentrations (procalcitonin < 2 ng mL(-1)) continuous veno-venous haemodiafiltration did not cause a rise in procalcitonin. In patients with increased procalcitonin plasma concentrations (> 3 ng mL(-1)), the protein was removed through the polysulphone membrane, with a final clearance of 4 mL min(-1) after the initial adsorption period (clearance 0.4-0.9 mL min(-1) during the first hour of continuous veno-venous haemodiafiltration). Thus, on the average, approximately 10% of plasma concentrations were measurable in the filtrate ultimately. However, procalcitonin plasma levels were not significantly altered during continuous veno-venous haemodiafiltration (86% of the initial concentration after 24 h). Although procalcitonin is removed from the plasma during continuous veno-venous haemodiafiltration in measurable amounts plasma procalcitonin concentrations did not change significantly during haemodiafiltration. Procalcitonin thus can also be used as a diagnostic parameter in patients undergoing continuous veno-venous haemodiafiltration.