Anticoagulation use and the risk of stroke and major bleeding in patients on hemodialysis: From the VIVALDI, a population-based prospective cohort study.

Background: Evidence supporting the use of anticoagulation for the prevention of stroke and thromboembolism in patients with kidney failure on hemodialysis (HD) and atrial fibrillation (AF) is limited. We prospectively assessed the incidences of stroke and major bleeding, as well as anticoagulation strategies in patients on HD with AF.

Methods: We recruited 625 prevalent HD patients into a population-based observational cohort study.

Antithrombotic agents for primary and secondary prevention of cardiovascular events in patients with end-stage renal disease on chronic hemodialysis.

Background And Aims: Cardiovascular disease (CVD) is common in patients with end-stage renal disease (ESRD) on hemodialysis (HD). However, antithrombotic therapy to prevent CVD increases the risk of bleeding. We aimed to investigate the prevalence of CVD and the practice patterns of antithrombotic agents in patients with ESRD on HD.

Venous thromboembolism and vascular access thrombosis in patients with end-stage renal disease on maintenance hemodialysis: Cross-sectional results of the Vienna InVestigation of AtriaL fibrillation and thromboembolism in patients on hemoDIalysis (VIVALDI).

Background: Patients with end-stage renal disease (ESRD) on maintenance hemodialysis (HD) are at risk for occurrence of vascular access thrombosis and venous thromboembolism (VTE). Understanding the extent of these complications and identifying risk factors can help improve management strategies.

Methods: Adult HD patients were cross-sectionally recruited into the Vienna InVestigation of AtriaL fibrillation and thromboembolism in patients on hemoDIalysis (VIVALDI).

Prevalence of Atrial Fibrillation and Antithrombotic Therapy in Hemodialysis Patients: Cross-Sectional Results of the Vienna InVestigation of AtriaL Fibrillation and Thromboembolism in Patients on HemoDIalysis (VIVALDI).

Background: Atrial fibrillation (AF) adds significant risk of stroke and thromboembolism in patients on hemodialysis (HD). The aim of this study was to investigate the prevalence of AF in a population-based cohort of HD patients and practice patterns of antithrombotic therapy for stroke prevention in AF.

Methods: The Vienna InVestigation of AtriaL fibrillation and thromboembolism in patients on hemodialysis (VIVALDI), an ongoing prospective observational cohort study, investigates the prevalence of AF and the risk of thromboembolic events in HD patients in Vienna, Austria.

A randomized trial of iron isomaltoside 1000 versus oral iron in non-dialysis-dependent chronic kidney disease patients with anaemia.

Background: Iron deficiency anaemia is common in patients with non-dialysis-dependent chronic kidney disease (NDD-CKD) and is often treated with oral or intravenous (IV) iron therapy. This trial compared the efficacy and safety of IV iron isomaltoside 1000 (Monofer®) and oral iron in NDD-CKD patients with renal-related anaemia.

Methods: The trial was a Phase III open-label, comparative, multicentre, non-inferiority trial conducted in 351 iron-deficient NDD-CKD patients, randomized 2:1 to either iron isomaltoside 1000 (Group A) or iron sulphate administered as 100 mg elemental oral iron twice daily (200 mg daily) for 8 weeks (Group B).

Pre-implant biopsy predicts outcome of single-kidney transplantation independent of clinical donor variables.

Background: Pre-implant biopsy findings account for the discard of many donor kidneys although their clinical value is not fully understood. We retrospectively investigated the predictive value of pre-implant histology, which in our center was obtained for protocol purposes, not for transplant decisions, on long-term allograft and recipient outcome after single-kidney transplantation.

Methods: This single-center study included 628 consecutive adult recipients of 174 Expanded Criteria Donor (ECD) and 454 Standard Criteria Donor kidneys.

Lisinopril pharmacokinetics and erythropoietin requirement in haemodialysis patients.

Background: There is ongoing controversy whether angiotensin-converting enzyme inhibitors (ACE-I) contribute to anaemia by causing hyporesponsiveness to erythropoiesis-stimulating agents (ESA). However, it is unknown whether or not plasma levels or area under the curve (AUC) of ACE-I are associated with responsiveness to ESA therapy.

Materials And Methods: We examined the association between lisinopril AUC, lisinopril plasma levels and ESA requirements that was assessed using an ESA index [(ESA IU/week/body weight kg)/(haemoglobin g/dL)].

Significance of peritubular capillary, glomerular, and arteriolar C4d staining patterns in paraffin sections of early kidney transplant biopsies.

Background: Although diffuse linear C4d deposition in peritubular capillaries (PTCs) is a well-established criterion of alloantibody-mediated kidney transplant rejection, the actual relevance of focal or granular C4d deposits or staining outside PTC (glomeruli and arterioles) has yet to be established.

Methods: This study was designed to evaluate the diagnostic significance of such nontypical C4d staining patterns. A total of 539 early indication biopsies (329 kidney transplants) were analyzed by immunohistochemistry using a polyclonal anti-C4d antibody.

Acute infection with a single hepatitis C virus strain in dialysis patients: Analysis of adaptive immune response and viral variability.

Background/aims: While the adaptive immune response is crucial for spontaneous resolution of acute hepatitis C virus (HCV) infection, it also constitutes the driving force for viral escape. For acutely HCV-infected dialysis patients, little is known about the host response and its impact on viral evolution.

Methods: Four haemodialysis patients accidentally infected with the same HCV strain were prospectively investigated with respect to the clinical course, CD4+ and CD8+ T-cell responses, neutralizing antibodies, viral kinetics and sequence variability.

Predictors of new-onset decline in kidney function in a general middle-european population.

Background: Limited epidemiological data are available on predictors of new-onset kidney disease.

Methods: In this longitudinal cohort study, 17 375 apparently healthy volunteers of the general Viennese population (46.4% women, age range 20-84 years, men 20-89 years) performed a baseline examination at some time within the study period (1990-2005) and completed a median of two follow-up examinations [interquartile range (IQR) 1 to 4]; the median follow-up period was 7 years (IQR 4 to 11).

Rescue therapy with tacrolimus and mycophenolate mofetil does not prevent deterioration of graft function in C4d-positive chronic allograft nephropathy.

Background: Humoral alloresponses may contribute to chronic allograft nephropathy (CAN) in a subset of kidney transplant recipients. For chronic humoral rejection, the efficacy of rescue therapy with tacrolimus and mycophenolate mofetil has been suggested.

Methods: Eleven recipients with C4d-positive CAN (index biopsy performed after a median of 3 years posttransplantation), who had been on cyclosporine A-based immunosuppression, were converted to tacrolimus, and if not part of basal therapy, to mycophenolate mofetil.

Peritransplant immunoadsorption: a strategy enabling transplantation in highly sensitized crossmatch-positive cadaveric kidney allograft recipients.

Background: Kidney transplant recipients with a current positive complement-dependent cytotoxicity crossmatch (CDCXM) are at high risk for hyperacute rejection and graft loss. Immunoadsorption (IA) represents an efficient strategy to remove donor-specific alloantibodies. In this analysis, we evaluated effectiveness of peritransplant IA as an anti-humoral strategy to overcome a current positive CDCXM in presensitized renal allograft recipients.

Iron overload in kidney transplants: prospective analysis of biochemical and genetic markers.

Background: The prevalence of iron overload and the influence of mutations in the HFE and TRF2 gene on biochemical markers of iron overload among renal transplant patients is unknown.

Methods: Serum iron, ferritin, transferrin saturation (TSAT), and liver function parameters were analyzed in a cohort of 438 renal transplants. In patients with iron overload, the time course of biochemical markers of iron status as well as the influence of iron loading mutations was investigated during a time period of 5 years.

Antibody maturation and viremia after primary cytomegalovirus infection, in immunocompetent patients and kidney-transplant patients.

To investigate antibody maturation and serum levels of cytomegalovirus (CMV) DNA after primary CMV infection, we studied 51 immunocompetent and 27 kidney-transplant patients. Compared with the immunocompetent patients, the transplant patients had significantly more-prolonged and -variable antibody maturation, clearly longer durations of viremia, and higher levels of CMV DNA; however, antibody maturation continued for >1 year even in immunocompetent patients. Long-term ganciclovir prophylaxis in the transplant patients was associated with either delayed immunoglobulin-G seroconversion, inhibition of antibody maturation (n=2), or immunoglobulin-class switching (n=1).

Risk factors for capillary C4d deposition in kidney allografts: evaluation of a large study cohort.

Background: Capillary deposition of the complement split product C4d has turned out to be a valuable marker of antibody-mediated rejection. The impact of pre- and posttransplant variables including particular immunosuppressive regimens on the frequency of C4d deposition has not yet been systematically investigated in a large multivariate analysis.

Methods: In this retrospective study, the authors evaluated the incidence of C4d deposition in 388 kidney transplant recipients subjected to diagnostic biopsy within the first 6 months and analyzed the influence of potential confounders on the rate of C4d-positive graft dysfunction by applying multivariate logistic regression.

Dose-dependent effect of parenteral iron therapy on bleomycin-detectable iron in immune apheresis patients.

Background: Iron deficiency and anemia are commonly encountered in patients with autoimmune diseases undergoing immune apheresis. This makes erythropoietin and iron substitution necessary in most patients. However, intravenous iron therapy may result in an increase of potentially toxic nontransferrin-bound iron.

Patient and graft survival in older kidney transplant recipients: does age matter?

An increasing gap between supply and demand of donor kidneys for transplantation exists. There is concern regarding the allocation of scarce organs to elderly patients, because the benefit obtained by the transplant may be less in elderly compared with younger recipients. It was the objective of this study to determine differences in patient and organ survival between organ recipients >65 yr and 50 to 64 yr of age at transplantation.

Viral features of lamivudine resistant hepatitis B genotypes A and D.

Viral differences among lamivudine resistant hepatitis B (HBV) genotypes have not been yet investigated. Therefore, we analyzed the characteristics of these viral strains in vivo. Forty-one patients carrying lamivudine resistant HBV were enrolled.

Impairment of transendothelial leukocyte migration by iron complexes.

Although iron sucrose and iron gluconate are generally well tolerated in patients who are treated for renal anemia, recent clinical studies and cell culture experiments suggested significant toxicity and long-term side effects arising from the use of these iron complexes. Because of the possible role of iron in infection or cardiovascular disease, it was theorized that parenteral iron compounds influence endothelial and PMN interaction in vitro. A well-established double-chamber method was used to assess the effect of different concentrations of iron sucrose and iron gluconate (1, 25, 50, and 100 micro g/ml) on the transendothelial migration of PMN.

TGF-beta1 impairs homocysteine metabolism in human renal cells: possible implications for transplantation.

We hypothesized that TGF-beta1 influences the metabolism of homocysteine (Hcy) and increases its cellular export, which may lead to hyperhomocysteinemia in patients with renal transplants. We exposed human renal proximal tubule epithelial cells (huRPTECs) to different concentrations of TGF-beta1, IL-1alpha, IL-10, or methionine and measured total Hcy (tHcy) in culture supernatants. We then examined the relationship between plasma levels of tHcy and TGF-beta1 in renal graft recipients.

Zoledronic acid to prevent bone loss in the first 6 months after renal transplantation.

Background: Bisphosphonates can prevent bone mineral density loss after renal transplantation, but their effect on trabecular mineralization and bone morphology, two key factors of bone stability, remains unknown.

Methods: In a 6-month, randomized, placebo-controlled study, 20 kidney transplant recipients received either 4 mg zoledronic acid or placebo twice within 3 months after engraftment. At transplantation and after 6 months, mean trabecular calcium concentration and trabecular morphometry were measured in bone biopsies.

Chronic hepatitis B virus infection in renal transplant recipients.

Although in Western Europe and North America the prevalence of chronic hepatitis B virus (HBV) infection has declined in patients awaiting renal transplantation, it remains a relevant clinical problem, mainly in patients with a long history of renal replacement therapy (RRT) who may have been infected many years ago. At the same time, a significant proportion of renal transplant recipients (RTR) is at risk for HBV infection in areas with endemic HBV. HBV infection may increase morbidity and mortality in RTR.

Influence of mycophenolic acid and tacrolimus on homocysteine metabolism.

Background: The effect of mycophenolate mofetil (MMF) on homocysteine (Hcy) metabolism is unknown.

Methods: This in vitro study examined whether mycophenolic acid or tacrolimus influences the formation of Hcy as determined by measuring the total Hcy (tHcy) concentrations in supernatants of human renal proximal tubule epithelial cells. Cells were incubated with and without vitamins (folate, vitamin B6 and B12) in the presence of low or high methionine concentrations at different mycophenolic acid (0, or 5, or 20 microg/mL) or tacrolimus (0, or 10, or 25 ng/mL) concentrations for 24, 48 or 72 hours.