Performance and Hemocompatibility of a Novel Polysulfone Dialyzer: A Randomized Controlled Trial.

Background: High-flux dialyzers effectively remove uremic toxins, are hemocompatible to minimize intradialytic humoral and cellular stimulation, and have long-term effects on patient outcomes. A new dialyzer with a modified membrane surface has been tested for performance and hemocompatibility. Methods: This multicenter, prospective, randomized, crossover study involved the application of the new polysulfone-based FX CorAL 600 (Fresenius Medical Care, Bad Homburg, Germany), the polyarylethersulfone-based Polyflux 170H (Baxter Healthcare Corporation, Deerfield, IL), and the cellulose triacetate-based SureFlux 17UX (Nipro Medical Europe, Mechelen, Belgium), for 1 week each, to assess the noninferiority of the FX CorAL 600's removal rate of ß2-microglobulin. Performance was assessed by removal rate and clearance of small- and medium-sized molecules. Hemocompatibility was assessed through markers of complement, cell activation, contact activation, and coagulation. Results: Of 70 patients, 58 composed the intention-to-treat population. The FX CorAL 600's removal rate of ß2-microglobulin was noninferior to both comparators (P<0.001 versus SureFlux 17UX; P=0.0006 versus Polyflux 170H), and superior to the SureFlux 17UX. The activation of C3a and C5a with FX CorAL 600 was significantly lower 15 minutes after treatment start than with SureFlux 17UX. The activation of sC5b-9 with FX CorAL 600 was significantly lower over the whole treatment than with SureFlux 17UX, and lower after 60 minutes than with the Polyflux 170H. The treatments with FX CorAL 600 were well tolerated. Conclusions: FX CorAL 600 efficiently removed small- and medium-sized molecules, showed a favorable hemocompatibility profile, and was associated with a low frequency of adverse events in this study, with a limited patient number and follow-up time. Further studies, with longer observation times, are warranted to provide further evidence supporting the use of the new dialyzer in a wide range of therapeutic options, and for long-term treatment of patients on hemodialysis, to minimize the potential effects on inflammatory processes.

Different kinetics of HBV and HCV during haemodialysis and absence of seronegative viral hepatitis in patients with end-stage renal disease.

BACKGROUND: Hepatitis C virus (HCV) and hepatitis B virus (HBV) infections are common in haemodialysis units. Moreover, some studies reported seronegative cases of viral hepatitis. We and others have previously shown an HCV RNA decline during haemodialysis; however, limited data on HBV viraemia during haemodialysis are available. METHODS: A total of 142 haemodialysis patients participated in this study, 11 were anti-HCV positive and 7 were HBsAg positive. HCV RNA and HBV DNA were determined in all patients irrespective of hepatitis serology. HBV DNA, HCV RNA, HBsAg and HCV core antigen (HCVcoreAg) were quantified repeatedly in anti-HCV- and HBsAg-positive patients before and after haemodialysis. RESULTS: No case of seronegative viral hepatitis could be identified. HCV RNA was detected in 9 of the 11 anti-HCV-positive patients, while HBV DNA tested positive in all 7 HBsAg-positive patients. A decrease of HCVcoreAg was observed during four dialysis sessions in 8/9 patients (-24.4 ± 22.7%, P < 0.001) parallelled by HCV RNA decline in most individuals (-10.1 ± 48.6%, P = 0.22). In contrast, HBV DNA and HBsAg declined only in 1/7 patients during all four independent measurements. The remaining six patients showed heterogeneous patterns of HBV DNA and HBsAg before and after haemodialysis without a significant change in mean HBV DNA and HBsAg levels (+14 ± 60.6% and -0.2 ± 25.3%, P > 0.05, respectively). HCVcoreAg correlated strongly with HCV RNA (r = 0.937; P < 0.001, n = 72), while there was no correlation between HBV DNA and HBsAg (r = -0.234; P = 0.131, n = 43). CONCLUSIONS: Seronegative viral hepatitis is rare in German maintenance haemodialysis patients. HCV RNA and HCVcoreAg decline during haemodialysis indicating a potential beneficial effect of haemodialysis during antiviral therapy of hepatitis C, which does not apply to HBV infection.

Kinetics of hepatitis C viral RNA and HCV-antigen during dialysis sessions: evidence for differential viral load reduction on dialysis.

Hepatitis C infection is a common problem in dialysis units. The prevalence ranges from 3% to more than 50%. Several reports have described a variable reduction of HCV-RNA during hemodialysis treatment sessions. But so far nothing is known about the HCV antigenemia or the kinetics of the reduction of HCV-RNA and HCV antigenemia during these sessions. HCV-RNA was monitored using the VERSANT HCV bDNA assay 3.0 (Bayer Healthcare Diagnostics, Leverkusen, Germany) or the HCV-Monitor TaqMan (Roche Diagnostics). HCV antigenemia was tested by using Ortho-trac-C assay (Ortho Clinical Diagnostics, Neckargemünd, Germany). Kinetics of HCV-RNA were available in 15 dialysis sessions measured by bDNA assay and in 5 dialysis sessions measured by rt-PCR. Quantitative HCV-antigenemia was available in fourteen dialysis sessions. Not only HCV-RNA but as expected also the HCV-antigenemia fell during the dialysis session. However, while the average reduction of HCV-antigen appears steady and linear, the level of HCV-RNA seems to be stable during the first 3 hr of dialysis, and decreases rapidly during the last 2 hr. The results seem to be independent of the HCV-RNA detection method. The different kinetics of HCV RNA and HCV antigen load suggest that there are different mechanisms responsible for the reduction of the HCV antigen and HCV-RNA, respectively. Reduction of viral load during dialysis session indicates a potential benefit of dialysis in case of HCV associated antiviral therapy.