Chronic induction of C-reactive protein by hemodialysis, but not by peritoneal dialysis therapy

.Objective: Evaluation of the inflammatory activity in patients on chronic peritoneal dialysis (PD) and patients on chronic hemodialysis (HD) in comparison to patients with chronic renal insufficiency without dialysis treatment and healthy volunteers..Design: Open, non randomized prospective study..Setting: Nephrology Department, including HD and PD therapy in a university hospital..Patients: Twenty-four patients on chronic PD, 21 patients on chronic HD therapy using a cuprophan dialyzer, 16 patients with chronic renal insufficiency without dialysis treatment, and 33 healthy volunteers; 8 additional patients before and after initiation of chronic HD therapy. All patients and controls were without infection or immunosuppressive therapy..Main Outcome Measures: As a marker of the inflammatory activity in the different patient groups, C-reactive protein (CAP) was measured serially using a sensitive, enzyme-Iinked, immunosorbent assay in order to detect values below the detection limit of standard assays..Results: All patient groups had CAP levels higher than the normal controls (p < 0.01). Patients on HD had CAP levels significantly higher than PD patients (p < 0.01) whose levels were comparable to patients without dialysis therapy. Accordingly, longitudinal meas urements before and after initiation of chronic HD showed a significant increase in CAP levels after the beginning of HD treatment (p < 0.04)..Conclusions: The results suggest that induction of the inflammatory activity is lower during PD compared to HD, since stimulation by the dialyzer membrane, dialysate buffer, or bacterial fragments in the dialysate is avoided. This observation might indicate a possible lower risk of long-term complications in patients with PD