Rainer Woitas - Academia.edu (original) (raw)

Papers by Rainer Woitas

BMC Nephrology, Mar 11, 2021

Background: Residual renal function is closely linked to quality of life, morbidity and mortality... more Background: Residual renal function is closely linked to quality of life, morbidity and mortality in dialysis patients. Beta-trace protein (BTP), a low molecular weight protein, has been suggested as marker of residual renal function, in particular in patients on hemodialysis. We hypothesized that BTP also serves as a marker of residual renal function in pertioneal dialysis patients. Methods: In this study 34 adult patients on peritoneal dialysis were included. BTP, creatinine, cystatin C and urea concentrations were analyzed simultaneously in serum and dialysate to calculate renal and peritoneal removal of the analytes. Results: In peritoneal dialysis patients with residual diuresis, mean serum BTP was 8.16 mg/l (SD ± 4.75 mg/l). BTP correlated inversely with residual diuresis (r s = − 0.58, p < 0.001), residual creatinine clearance (Cl Cr) (r s = − 0.69, p < 0.001) and total urea clearance (Cl urea) (r s = − 0.56, p < 0.001). Mean peritoneal removal of BTP was 3.36 L/ week/1.73m 2 (SD ± 1.38) and mean renal removal 15.14 L/week/1.73m 2 (SD ± 12.65) demonstrating a significant renal contribution to the total removal. Finally, serum BTP inversely correlated with alterations in residual diuresis (r = − 0.41, p = 0.035) and renal creatinine clearance over time (r = − 0.79, p = p < 0.001). Conclusion: BTP measurement in the serum may be a simple tool to assess residual renal function in peritoneal dialysis patients.

Nephrology Dialysis Transplantation

Background and Aims There are research data suggesting a citrate-buffered dialysis bath being sup... more Background and Aims There are research data suggesting a citrate-buffered dialysis bath being superior to conventional acetate-buffered dialysis. Since Heparin may lead to bleeding complications and increased costs we focused on potential Heparin savings in a cohort of 100 dialysis patients who systematically were examined in a 48 weeks comprising timeframe using a citrate-buffered dialysis bath. Method Stable dialysis patients (n = 100, 30 females, mean age 70.7 yrs.) who were treated by high flux dialysis were switched from conventional acetate-buffered dialysis (3mmol/l acetate) to a citrate-buffered dialysis bath (0.8 mmol/l citrate, 0.3 mmol/l acetate; MTN, Neubrandenburg, Germany). After a 4 weeks run-in phase on the new dialysis bath the heparin-dosing was systematically reduced. Heparin was given as a single shot prior to the start of dialysis, the dialysate flow was set on 500 mL/min constantly. Heparin-dosing in the time course was assessed on the basis of the run-in phase...

The Journal of Immunology

Since an efficient control of virus infections may depend on the appropriate lymphokine profile, ... more Since an efficient control of virus infections may depend on the appropriate lymphokine profile, we studied cytokine responses and CD30 induction, a recently proposed surrogate marker of type 2 cells, in 10 healthy anti-hepatitis C virus (HCV)-seropositive blood donors without viremia (group A) and in 15 patients with hepatitis C (group B). Intracytoplasmic IFN-gamma, IL-2, IL-4, and IL-10 were determined by triple-color flow cytometry in the CD3+ and CD3+/CD30+ lymphocyte subsets after stimulation of PBMC with rHCV core protein and five core-derived peptides corresponding to the four immunodominant Th epitopes C.T1 to C.T4. In group A, more type 1 cytokines were induced by the rHCV core protein and all immunodominant core peptides (p < 0.05), whereas IL-10-producing T cells were found more frequently in group B. Induction of CD30+ T cells was found almost exclusively in group B (p < 0.01). The difference in cytokine responses was due to the CD3+/CD30- T cell subset and not th...

Nephrology

BackgroundBeta Trace Protein (BTP) is a biomarker for residual kidney function which has been lin... more BackgroundBeta Trace Protein (BTP) is a biomarker for residual kidney function which has been linked to cardiovascular and all‐cause mortality in haemodialysis patients. Following renal transplantation, recipients remain at increased risk for cardiovascular events compared with the general population. We aimed to determine the relationship of pre‐transplant BTP to major adverse cardiac events (MACE) in patients following kidney transplantation.MethodsWe included 384 patients with end‐stage renal disease who received a kidney transplant. MACE was defined as myocardial infarction (ST‐segment elevation or non‐ST‐segment elevation, stroke or transient ischemic attack), coronary artery disease requiring intervention or bypass or death for cardiovascular reason. The association between pre‐transplant serum BTP concentration and post‐transplant MACE was evaluated by Kaplan–Meier and Cox regression analyses.ResultsPost‐transplant MACE occurred in 70/384 patients. Pre‐transplant BTP was sign...

SSRN Electronic Journal, 2021

Background: We previously reported excellent efficacy and improved safety aspects of rapid steroi... more Background: We previously reported excellent efficacy and improved safety aspects of rapid steroid withdrawal (RSWD) in the randomized controlled one year “Harmony” trial, in which 587 predominantly deceased-donor kidney transplant recipients were randomized either to basiliximab or rabbit ATG induction therapy and compared to standard immunosuppressive therapy consisting of basiliximab, low tacrolimus once daily, mycophenolate mofetil, and corticosteroids. Methods: Following the end of the original one-year study period, patients were asked to participate in the observational follow-up (FU) study examining most of the end points of the original study. Hereby, de novo incidences between year one and three as well as year three and five were assessed at the three-/five-year visits, respectively. Findings: Biopsy-proven acute rejection and death-censored graft survival rates remained low and independent of RSWD. RSWD was an independent positive factor for patient survival (adjusted ha...

Journal of Laboratory and Precision Medicine, 2017

Zeitschrift für Gastroenterologie, 2005

Zeitschrift für Gastroenterologie, 2004

Lancet (London, England), Dec 17, 2016

Standard practice for immunosuppressive therapy after renal transplantation is quadruple therapy ... more Standard practice for immunosuppressive therapy after renal transplantation is quadruple therapy using antibody induction, low-dose tacrolimus, mycophenolate mofetil, and corticosteroids. Long-term steroid intake significantly increases cardiovascular risk factors with negative effects on the outcome, especially post-transplantation diabetes associated with morbidity and mortality. In this trial, we examined the efficacy and safety parameters of rapid steroid withdrawal after induction therapy with either rabbit antithymocyte globulin (rabbit ATG) or basiliximab in immunologically low-risk patients during the first year after kidney transplantation. In this open-label, multicentre, randomised controlled trial, we randomly assigned renal transplant recipients in a 1:1:1 ratio to receive either basiliximab induction with low-dose tacrolimus, mycophenolate mofetil, and steroid maintenance therapy (arm A), rapid corticosteroid withdrawal on day 8 (arm B), or rapid corticosteroid withdra...

Journal of Hepatology, 1998

Journal of Hepatology, 2004

Gastroenterology, 1998

Backoround: A differential activation of T ceil subsets and cytokine induction may be responsible... more Backoround: A differential activation of T ceil subsets and cytokine induction may be responsible for different outcomes in hepatitis C. Method: We analyzed the hepatitis C (HCV) specific immune response to the recombinant HCV proteins core, NS3, NS4, NS5a and NS5b in peripheral blood lymphocytes (PBL) of 29 patients with chronic hepatitis C (group 1) and 8 patients with Self-limited HCV infection (group2). T-cell subset expansion of the common T-cell receptors VI32, VI33, VI35, VI36.1, VI38, VI313.1, V[313.6, VI314, VI317, VI321.3 as well as intracytoplasmic expression of IL-2, IFN-y, TNF-ct, IL-4 and IL-10 were determined in CD45RO ÷ T cells at the single cell level by fluorescence activated cell sorting. Data are given as mean stimulation index with standard error of the mean (SI-+ SEM) and statistical analysis was done by Mann-Whitney U test. Results: In patients with chronic hepatitis C the TCR V~8 + subset expanded significantly after stimulation with all HCV proteins (p<0.05, groupl vs. group2, SI -+ SEM: Core: 3.1 -+ 1.1 vs. 0.7 -+ 0.1, NS3 4.7 2.2 vs. 0.8 -+ 0.2, NS4 3.8 -+ 1.5 vs. 1.1 +0.7, NS5a 5.9 -+ 1.9 vs. 0.8 -+ 0.1, NS5b 8.6 -+ 3.1 vs. 1.0 -+ 0.2). By contrast, after stimulation with NS3 VI32 + and VI36.1 ÷ T cells expanded significantly in patients of group 2 (p<0.05, groupl vs. group2: V132 0.9 + 0,1 vs. 1.5 -+ 0.4, VI36.1 0.8 +-. 0,1 vs. 2.9 -+ 0.7). In this group TCR V132 +, V1314 + and V1321.3 ÷ T cells were also induced significantly after stimulation with NS5b (p<0.05, groupl vs. group2:VI32 1.0-+0.1 vs. 1.7-+0.3, VI314 0.9-+0.1 vs. 3.6-+1.5, V1321.3 1.1-+0.1 vs. 2.0+0.4). All other tested T cell subsets did not expand significantly after stimulation with hepatitis C proteins in both patient groups. In group 2 the simultaneous analysis of cytokines revealed a stronger IL-2 response (p<0.05) after stimulation with all HCV proteins, a stronger IFN-7 (p<0.05) and TNF-ct (p<0.05) response to core and NS3 protein. However, a preferential cytokine production could not be allocated to expansion of a particular T cell subset. Conclusion: Our data indicate differential HCV-specific expansion of T cell subsets, which may be related to the different outcome of HCV infection in our two groups. However, these differences in the activation of T cell subsets do not explain the preferential type 1 cytokine pattern in patients with selflimited disease.