Lutz Liefeldt

Charité Universitätsmedizin Berlin, Berlin, Land Berlin, Germany

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Publications (38)196.86 Total impact

  • Article: A randomized trial of intensified vs. standard dosing for enteric-coated mycophenolate sodium in de novo kidney transplant recipients: results at 1 year.
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    ABSTRACT: In a 6-month prospective, openlabel, multicenter study, 128 de novo kidney transplant patients receiving cyclosporine (CsA) and steroids were randomized to an intensified regimen of enteric-coated mycophenolate sodium (EC-MPS) or to a standard EC-MPS regimen to Week 6 posttransplant, after which the regimen was identical. In a follow-up study to Month 12 post-transplant (49 intensified regimen, 52 standard regimen), the reduced rate of BPAR observed at Month 6 (intensified regimen 3.2%, standard regimen 16.9%, p = 0.016) was maintained at Month 12 (4.8% vs. 18.5%, p = 0.026). Estimated GFR (Cockcroft-Gault) at Month 12 was comparable in the intensified group (mean (SD) 54.8 (22.9) ml/min) vs. the standard group (mean (SD) 57.5 (23.6) ml/min, p = 0.83). The incidence of adverse events and serious adverse events at Month 12 was similar in both treatment groups, although adverse events with a suspected relation to study drug were reported in 69.8% and 50.8% of patients in the intensified and standard regimen groups, respectively (p = 0.032). Infections and hematological parameters were similar between groups. In conclusion, an early regimen of intensified EC-MPS with CsA and steroids achieves a low rate of BPAR over the first year after kidney transplantation with similar renal function to a standard regimen, and without a clinically relevant impact on safety.
    Clinical nephrology 04/2013; · 1.17 Impact Factor
  • Article: An evaluation of sirolimus in renal transplantation.
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    ABSTRACT: Introduction: Sirolimus is a powerful antiproliferative immunosuppressive drug approved for the prevention of kidney allograft rejection. By its unique mechanism of action, sirolimus provides a multitude of clinical potential and has been used effectively in different drug combinations. Extensive experience has been gained regarding the best timing of its application, side effect profile and potential benefits and limitations compared with other immunosuppressive drugs. Areas covered: The authors evaluate the recent experience with sirolimus in kidney transplantation. Pivotal randomized controlled trials were used to provide an overview with special attention to pharmacokinetic and dynamic aspects of sirolimus, its current clinical use as well as perspectives for its future role. Expert opinion: Sirolimus enriches the possibilities of immunosuppressive therapies after renal transplantation. Beneficial effects toward kidney function by allowing CNI sparing, lower incidence of malignancies and less viral infections have been suggested. Sirolimus should be used cautiously in de novo patients for reasons of wound healing. An early conversion to a sirolimus-based CNI-free regimen has shown promising results, whereas late conversion is more challenging. Finally, sirolimus-associated side effects are causing tolerability concerns and frequent discontinuations. Future research should aim to better define the therapeutic window and those patients most likely to benefit.
    Expert Opinion on Drug Metabolism &amp Toxicology 08/2012; 8(10):1337-56. · 3.12 Impact Factor
  • Article: Identification and therapeutic management of highly sensitized patients undergoing renal transplantation.
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    ABSTRACT: Sensitization is generally referred to as the development of alloantibodies, specifically anti-human leukocyte antigen (HLA) immunoglobulin G (IgG) antibodies, most commonly caused by pregnancy, blood transfusion or a previous transplant. Despite being a well known phenomenon, there has not been a general consensus on its definition, monitoring or management. Today, 25% of the patients waitlisted for kidney transplant in the US have a panel reactive antibody (PRA) of >10% while, in the Eurotransplant zone, 14% have a PRA of >5%. Sensitized patients have more difficulty in finding a well HLA-matched donor, and have a higher risk of experiencing longer waiting times, more rejection episodes and eventually inferior long-term graft or patient survival. We review the currently available strategies in identifying and managing highly sensitized patients undergoing renal transplantation. We discuss the progress and limitations in laboratory techniques to elaborate on challenges in defining sensitized patients. The main management options (i.e. the Acceptable Mismatch Program, donor exchange programmes and the desensitization approach) and their mechanisms, related policies, advantages and outcomes, as well as medications and methods being investigated, are updated. In addition, particular emphasis is given to sensitization prevention, a practice that is neglected with our increasing ability to suppress the immune system.
    Drugs 07/2012; 72(10):1335-54. · 4.23 Impact Factor
  • Article: Outcomes after laparoscopic living donor nephrectomy: comparison of two laparoscopic surgeons with different levels of expertise.
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    ABSTRACT: Study Type - Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Laparoscopic living donor nephrectomy has evolved as the procurement method of choice for living kidney donation. Given that this is a technically challenging procedure with potential risks for the healthy donor, skills transfer from an experienced laparoscopist to a novice is critical. The present study investigates donor and recipient outcomes during a novice's early experience with this procedure. Previous training in laparoscopic renal surgery and mentoring by the expert helps the novice to generate acceptable outcomes. However, longer warm ischaemia times during the learning phase may affect short-term graft function. OBJECTIVE: •  To test the effect of surgeon experience on donor and recipient outcomes after laparoscopic living donor nephrectomy (LLDN). Results of a LLDN expert were compared with those of an LLDN novice. PATIENTS AND METHODS: •  Between October 2008 and October 2010 the last 20 cases of a series of 130 consecutive LLDNs, performed by an expert (EXP) were compared with the first 20 cases of an LLDN novice (NOV). •  Donor and recipient outcomes were evaluated. •  The novice was mentored by the expert during his initial four LLDN cases. RESULTS: •  Donor and recipient demographics were not different between the two surgeon groups. •  Total operating time and warm ischaemia time during LLDN was significantly longer in the NOV group compared with the EXP group (273 min vs 147 min and 213 s vs 162 s, respectively). •  The incidence of donor complications was low in both groups. Length of hospital stay among donors did not differ between groups. •  Although delayed graft function, rejection rates and postoperative serum creatinine levels indicated slightly poorer recipient outcomes in the NOV group, differences did not reach statistical significance. CONCLUSIONS: •  Mentoring by an experienced urological laparoscopist may help an LLDN novice to generate acceptable donor and recipient outcomes. •  Whether or not prolonged operating times and warm ischaemia times during the early phase of an LLDN experience are risk factors for impaired graft function needs further evaluation.
    BJU International 07/2012; · 2.84 Impact Factor
  • Article: Non-invasive imaging of living kidney donors: intraindividual comparison of multislice computed tomography angiography with magnetic resonance angiography.
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    ABSTRACT: Evaluation of vascular variants is crucial for donor assessment prior to living kidney transplantation. Both contrast-enhanced (CE) magnetic resonance angiography (MRA) and multislice computed tomography (MSCT) are currently used for imaging living kidney donors. Aim of this study was the comparison of the accuracy of MSCT angiography and CE-MRA for the assessment of renal vascular anatomy. Prospective study at a university transplant center including 65 potential living kidney donors. Pre-operative imaging by MSCT angiography and CE-MRA was correlated with the findings of laparoscopic donor nephrectomy in 48 donors. MSCT detected significantly more patients and more kidneys with accessory arteries than CE-MRA (p < 0.05). MSCT and CE-MRA performed similarly in identifying venous and ureteral abnormalities. The overall sensitivity, specificity, and accuracy for identifying accessory arteries were 85%/97%/94% for MSCT and 54%/97%/85% for CE-MRA. The sensitivity, specificity, and accuracy for the identification of supernumerary veins were 67%/95%/92% for MSCT and 67%/98%/94% for CE-MRA, respectively. We found MSCT angiography to be more sensitive and accurate than CE-MRA in the detection of supernumerary arteries prior to living donor nephrectomy.
    Clinical Transplantation 07/2012; 26(4):E412-7. · 1.67 Impact Factor
  • Article: Accumulation of elderly ESRD patients with blood group O on the waiting list.
    Lutz Liefeldt, Klemens Budde, Petra Glander
    Transplant International 10/2011; 24(10):e83-4. · 2.92 Impact Factor
  • Article: Inosine 5'-monophosphate dehydrogenase activity as a biomarker in the field of transplantation.
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    ABSTRACT: Inosine 5'monophosphate dehydrogenase (IMPDH) is the rate limiting enzyme in the de novo synthesis of guanine nucleotides. The direct determination of target enzyme activity as a biomarker of mycophenolic acid (MPA) may help to estimate better the individual response to the immunosuppressant. However, the assessment of the clinical utility of this approach is limited by the diversity of the assay systems, which has not yet allowed the prospective assessment of this enzyme in larger patient cohorts. A recently validated and standardized assay allows the investigation of IMPDH activity in larger clinical studies. Although descriptive results from observational studies hold promise for a more individualized therapy in transplant medicine, more studies are needed to prospectively validate this approach.
    Clinica chimica acta; international journal of clinical chemistry 08/2011; 413(17-18):1391-7. · 2.54 Impact Factor
  • Article: Comparison between bortezomib and rituximab in the treatment of antibody-mediated renal allograft rejection.
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    ABSTRACT: Antibody-mediated rejection (ABMR) following kidney transplantation is associated with poor allograft survival. Conventional treatment based on plasmapheresis (PPH) and the administration of intravenous immunoglobulins (IVIG) is not satisfactory. Two compounds, more specifically targeting B cells and plasma cells, may help to improve the prognosis: rituximab, a B-cell-depleting monoclonal antibody, and bortezomib, a proteasome inhibitor causing apoptosis of plasma cells. Starting in February 2009, we treated 10 consecutive patients with ABMR according to current Banff criteria with one cycle of bortezomib [1.3 mg/m(2) intravenously (i.v.), Day 1, 4, 8, 11]. This group was compared to a historical control group of patients (n = 9) treated with a fixed single dose of rituximab (500 mg i.v.). All patients received PPH (6×) and IVIG (30 g). Patients with acute ABMR additionally received methylprednisolone (3 × 500 mg i.v.). Patient survival in both groups was 100%. At 18 months after treatment, graft survival was 6/10 in the bortezomib group as compared to 1/9 functioning grafts in the rituximab group (P = 0.071). Renal function was superior in patients treated with bortezomib as compared to rituximab-treated patients (serum creatinine at 9 months: 2.5 ± 0.6 versus 5.1 ± 2.1 mg/dL, P = 0.008). Proteinuria was not different between both groups (9 months: 1.3 ± 1.0 versus 1.6 ± 1.6 g/day, P = n.s.). Treatment of ABMR with bortezomib in addition to standard therapy was partially effective, whereas treatment with a fixed dose of rituximab in addition to standard therapy with PPH and IVIG did not result in sufficient long-term graft survival. In the future, new strategies including the combination of both substances and the application of higher doses must be discussed.
    Nephrology Dialysis Transplantation 08/2011; 27(3):1246-51. · 3.40 Impact Factor
  • Article: Erratum to: No need for systemic heparinization during laparoscopic donor nephrectomy with short warm ischemia time.
    World Journal of Urology 08/2011; 29(4):567. · 2.41 Impact Factor
  • Article: No need for systemic heparinization during laparoscopic donor nephrectomy with short warm ischemia time.
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    ABSTRACT: Systemic heparin administration during laparoscopic donor nephrectomy (LDN) may prevent microvascular thrombus formation following warm ischemia. We herein present our experience with and without systemic heparinization during LDN. We retrospectively reviewed donor complications and graft outcomes in 119 consecutive live donor kidney transplantations between January 2005 and December 2009. Systemic heparin was administered to the first 65 donors. LDN was carried out by 2 surgeons using a pure laparoscopic technique. Total operating time for LDN was significantly longer in the heparin group (202 vs. 157 min). The incidence of renal artery multiplicity was significantly higher in the heparin group. Mean warm ischemia time was 160 s, and mean hospital stay was 5 days with no differences between groups. Postoperative hemorrhage occurred in 3 donors with systemic heparinization and in 1 without heparinization. Two donors received blood transfusions, and 2 underwent laparoscopic reexploration. Three grafts were lost in the heparin group and 1 in the non-heparin group. Graft loss was due to early vascular thrombosis (n = 3) and due to acute rejection (n = 1). Overall, 1-year graft survival was 96.6%, and 1-year serum creatinine was 1.41 mg/dl (P = n. s. between groups). Abandoning systemic donor heparinization in LDN with short warm ischemia has a low complication rate without adverse effects on short- and long-term graft outcomes.
    World Journal of Urology 05/2011; 29(4):561-6. · 2.41 Impact Factor
  • Article: Safety and efficacy of intensified versus standard dosing regimens of enteric-coated mycophenolate sodium in de novo renal transplant patients.
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    ABSTRACT: Efficacy and safety of an intensified dosing (ID) regimen of enteric-coated mycophenolate sodium (EC-MPS), which achieves higher mycophenolic acid exposure early posttransplantation, were evaluated in comparison with a standard dosing (SD) regimen. In total, 128 de novo kidney transplant recipients treated with basiliximab induction, cyclosporine A, and steroids were randomized (1:1) to receive EC-MPS as SD (1440 mg/day; n=65) or ID (days 0-14: 2880 mg/day; days 15-42: 2160 mg/day; followed by 1440 mg/day; n=63). Efficacy parameters, safety, and tolerability were assessed over a 6-month study period. The primary endpoint was mean time to first occurrence of treatment failure. Mean time to treatment failure was 130 days (95% confidence interval [CI]: 81-n/a) in the ID group versus 114 days (95% CI: 15-155) in the SD group (P=0.36). Similar percentages (ID 30.2%; SD 36.9%) experienced treatment failure. Biopsy-proven acute rejection occurred in 2 (3.2%) ID versus 11 (16.9%) SD patients (P<0.001). Three (2.3%) deaths (2 SD, 1 ID) and five (3.9%) graft losses (3 SD, 2 ID) occurred. Renal function, incidence of infection, and hematologic disorders were comparable in both study cohorts. Gastrointestinal disorders occurred in 51 (81.0%) ID and 49 (75.4%) SD patients with overall similar tolerability as assessed by the Gastrointestinal Symptom Rating Scale. In this exploratory study, the EC-MPS ID regimen reduced the incidence of rejection and showed a comparable safety and tolerability profile to SD. Further examination of this approach in a larger patient cohort is now warranted to confirm these findings.
    Transplantation 02/2011; 91(7):779-85. · 4.00 Impact Factor
  • Article: Risk factors for cardiovascular disease in renal transplant recipients and strategies to minimize risk.
    Lutz Liefeldt, Klemens Budde
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    ABSTRACT: Cardiovascular disease is the leading cause of death following renal transplantation, and renal transplant patients have a greatly increased cardiac risk compared with the general population. Death with a functioning graft caused by cardiovascular disease also represents a substantial cause of graft loss. Decreased renal function in transplant recipients is a major contributor to increased cardiac risk, both as an independent risk factor and because of its negative effects on hypertension, anemia, left ventricular hypertrophy, and dyslipidemia. Graft loss and diabetes mellitus are also significant risk factors for cardiac death. Although critical for maintaining the transplanted organs, standard immunosuppressants have toxicities that exacerbate cardiac risk. Preservation of renal function, prevention of graft loss, and reductions in cardiovascular risk factors via improvements in both patient management and immunosuppressive therapies constitute critical strategies for optimizing patient and graft survival over the long term.
    Transplant International 12/2010; 23(12):1191-204. · 2.92 Impact Factor
  • Article: Comparison of first and second kidney transplants from the same deceased donor.
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    ABSTRACT: Cold ischaemic time (CIT) may negatively influence graft function, increase the risk of acute rejection, and have adverse effects on graft and patient survival. This holds true especially for expanded criteria donors. As multi-centre studies on the impact of CIT are potentially biased, we performed a retrospective single-centre analysis of both kidneys from the same deceased donor transplanted consecutively into two recipients. A retrospective analysis of 80 kidneys from 40 donors transplanted into 80 recipients between January 1989 and December 2007 was conducted. Transplantations were performed successively due to logistic reasons resulting in a longer CIT for the second transplantation. We compared the outcome of the first (Rank 1) vs. the second (Rank 2) transplantation of the same donor. Ten donors/20 kidneys were allocated in the Eurotransplant Senior Program (ESP). Overall, no significant difference was found for the number of rejections, delayed graft function (DGF), functional data (creatinine, creatinine clearance and GFR) or graft survival despite a significant difference in CIT of Rank 1 recipients (8.3 h) vs. Rank 2 recipients (14.3 h). Subgroup analysis of kidneys transplanted in the Eurotransplant Senior Program (CIT Rank 1: 7 h vs. Rank 2: 12 h) also showed no difference for all the items studied. Donor kidneys ≥65 years transplanted at Rank 2 had a higher rate of DGF when compared with kidneys from donors <65 years transplanted at Rank 1, and function was better for the young Rank 1 recipients for all the time points measured. Graft- and patient survival did not differ. We found no difference between the successively transplanted kidneys of the same donor, not even for the expanded criteria donor organs. Nevertheless, assuming a 'safe' CIT is not justified, and CIT should always be kept as short as possible.
    Nephrology Dialysis Transplantation 12/2010; 25(12):4055-61. · 3.40 Impact Factor
  • Article: Enteric-coated mycophenolate sodium.
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    ABSTRACT: Mycophenolic acid (MPA) therapy is a fundamental component of most post-transplant immunosuppressive regimens. Side effects, however, are common and frequently necessitate dose reductions or discontinuations. Enteric-coated mycophenolate sodium (EC-MPS) is designed to improve the gastrointestinal (GI) tolerability of MPA. This review assesses the pharmacology, efficacy and safety of EC-MPS. An understanding of the use of EC-MPS in solid organ transplantation and the key trials examining the GI impact of EC-MPS versus the immediate-release mycophenolate mofetil (MMF) formulation. The article also addresses the possible impact of proton pump inhibitor therapy, and the optimal MPA dose with different concomitant immunosuppressants. Evidence from blinded trials using standard reporting measures or patient-reported outcomes has not confirmed a significant improvement in the GI symptom burden using EC-MPS. Several open-label studies, however, have consistently shown an improvement in GI tolerability with EC-MPS, which can permit restoration of the optimal MPA dose. EC-MPS has equal efficacy and possibly a different tolerability profile to MMF, thus offering a choice to physicians and their patients, particularly those experiencing MMF-related GI symptoms, diabetic patients or those in whom an MPA dose reduction is required.
    Expert Opinion on Drug Safety 11/2010; 9(6):981-94. · 3.02 Impact Factor
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    Article: The 'blood group O problem' in kidney transplantation--time to change?
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    ABSTRACT: Patients with blood group O have disadvantages in the allocation of deceased donor organs in the Eurotransplant Kidney Allocation System and fewer ABO-compatible living donors. In order to investigate the consequences of this dilemma, we analysed the outcome of patients with blood group O in our transplantation programme. A single-centre analysis of 1186 waitlisted patients for first deceased donor kidney transplantations between 1996 and 2008 was performed, and the mechanisms of blood group-dependent differences for graft and recipient outcome were assessed. Median follow-up time until death or end of observation for all waitlisted patients was 66 months (range, 0-158 months) and for 589 recipients of a kidney graft was 61 months (range, 0-158 months). Patients with blood group O had significantly longer waiting times for deceased donor kidney grafts, compared to non-group O recipients (median waiting time, 85 vs 59 months). As a consequence, blood group O patients had an increased risk for death without transplantation (13.1% for O patients vs 9.6% for non-O patients; P < 0.05). Despite a good human leukocyte antigen match, graft outcome tended to be worse in O recipients; 14.1% (95% CI, 8.2-19.9%) of all O kidneys from deceased donors were transplanted into non-O recipients, leading to the accumulation of O recipients on the waiting list. The export of blood group O donor kidneys to other blood groups leads to longer waiting times, to a higher death rate and to accumulation of blood group O patients on the waiting list, which will further aggravate the problem in the future. Our results should prompt further research on the issues associated with blood group O. Current allocation systems and living donor kidney exchange programmes should be re-evaluated to address this problem.
    Nephrology Dialysis Transplantation 06/2010; 25(6):1998-2004. · 3.40 Impact Factor
  • Article: Pharmacodynamic evaluation of the first dose of mycophenolate mofetil before kidney transplantation.
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    ABSTRACT: The effect of mycophenolate mofetil (MMF) on T cell function has not been evaluated in patients undergoing kidney transplantation. The aim of this study was to assess the effect of 1g of MMF on T cell function, that is, intralymphocyte cytokine expression, T cell activation (CD25 and CD71), and T cell proliferation, as well as inosine monophosphate dehydrogenase (IMPDH) activity, to better understand the relationship between pharmacokinetic and pharmacodynamic markers in patients receiving the first dose of MMF before kidney transplantation. Twenty-four patients undergoing a kidney transplantation from a living donor were enrolled in this study. Compared with baseline (before MMF intake), T cell proliferation (93%), IMPDH activity (74%), CD25 (46%), and CD71 (50%) expression significantly decreased during the first hour after MMF intake, in parallel to the rise in MPA concentration. Thereafter, all pharmacodynamic markers, except IMPDH activity, returned back to baseline level. There was a complex inverse relationship between pharmacokinetic and pharmacodynamic markers. The inhibition of T cell proliferation was highly correlated to IMPDH activity, but also to T cell activation markers. The administration of MMF to patients is associated not only with a dramatic decrease in both T cell proliferation and IMPDH activity, but also with in a decrease in CD25 and CD71 expression.
    Clinical Journal of the American Society of Nephrology 05/2009; 4(5):936-42. · 5.23 Impact Factor
  • Article: Anti-human leukocyte antigen and donor-specific antibodies detected by luminex posttransplant serve as biomarkers for chronic rejection of renal allografts.
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    ABSTRACT: Although the incidence of early acute rejection could have been diminished in the past, the long-term renal allograft survival could not benefit from the introduction of more effective immunosuppressive regimens mainly aiming at cellular rejection mechanisms. The cause of chronic rejection is still discussed controversially. Here, we demonstrate to what extent human leukocyte antigen (HLA) antibodies (HLAab) posttransplant contribute to late graft outcome. A total of 1014 deceased kidney transplant recipients transplanted at the Charité hospital were monitored in a cross-sectional manner for the development of HLAab using Luminex Single Antigen beads. Patients with stable kidney function at a median of 5-years posttransplant were tested once for HLAab and monitored for 5.5 years after testing. Thirty percent of recipients showed HLAab. Donor-specific antibodies (DSA) were found in 31% of antibody positive patients. The presence of DSA was associated with a significantly lower graft survival of 49% vs. 83% in the HLAab negative group (P< or =0.0001). Non-DSAs also had an adverse effect on graft survival (70% vs. 83%; P=0.0001). In a prospective analysis of 195 patients with repeatedly no detectable HLAab, the survival probability was 94% as opposed to 79% survival among patients who developed HLAab de novo after the first testing (P=0.05). We confirmed that HLAab produced even late after transplantation are detrimental to graft outcome. DSA were proven to have a strong adverse impact on graft survival. The results indicate that a posttransplant HLAab monitoring routine could be appropriate to improve long-term results.
    Transplantation 05/2009; 87(10):1505-13. · 4.00 Impact Factor
  • Article: Improved assay for the nonradioactive determination of inosine 5'-monophosphate dehydrogenase activity in peripheral blood mononuclear cells.
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    ABSTRACT: Mycophenolic acid (MPA) inhibits the enzyme inosine 5'-monophosphate dehydrogenase (IMPDH). Thus, the measurement of IMPDH activity could serve as a specific pharmacodynamic (PD) tool for monitoring MPA therapy. At present, however, monitoring of pharmacokinetic parameters is preferred over that of PD parameters because, in general, PD assays are labor-intensive and poorly reproducible. Currently, cell count or protein concentration is widely accepted as methods to normalize enzyme activity. In the present study, we have attempted to further improve a method for the determination of IMPDH activity to increase the robustness and reproducibility of the IMPDH activity assay itself, without making the assay more labor-intensive. Therefore, several aspects of the IMPDH method were investigated regarding their influence on the reproducibility and also modified to increase the feasibility and consistency of the assay. The isolation of peripheral blood mononuclear cells (PBMCs) of whole blood samples was found to be the most variable step. Normalization on cell count is labor-intensive and at the same time has a poor reproducibility. Determination of the protein content in cell extracts is impaired by contamination with extracellular proteins and non-PBMCs. Alternatively, the intracellular substance adenosine monophosphate (AMP) was investigated to normalize the newly generated xanthosine monophosphate. Among various subject groups, no significant differences in mean AMP concentration were found. To simplify the procedure, PBMCs were diluted to a fixed volume after isolation from sample of whole blood, and the IMPDH activity was normalized to the AMP concentration quantified in the same high-performance liquid chromatography run as xanthosine monophosphate was quantified. The within-run and total imprecision (coefficient of variation) ranged from 4.2% to 10.6% and from 6.6% to 11.9%, respectively. In conclusion, the modified method described here for the measurement of IMPDH activity can be used reliably in multicenter trials and in longitudinal studies to evaluate the additional value of any PD monitoring among a diversity of patients treated with MPA.
    Therapeutic drug monitoring 04/2009; 31(3):351-9. · 2.43 Impact Factor
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    Article: Gender-dependent impact of risk factors for cardiovascular and non-cardiovascular mortality in end-stage renal disease patients on haemodialysis.
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    ABSTRACT: We investigated whether mortality risk factors are gender dependent in haemodialysis patients. Patients (n = 230; 118 women, 112 men) on haemodialysis were followed for 52 months to assess the incidence of death due to cardiovascular or non-cardiovascular causes. Survival was compared by Cox regression analysis using age, diabetes, pre-existing coronary disease, troponin T and C-reactive protein as covariates. In total, 120 participants (52.2%) died within the 52 months of follow-up: 57 patients died of cardiovascular disease, 35 patients died of infectious diseases. Cox regression revealed that age, pre-existing coronary heart disease and troponin T were independent all-cause mortality risk factors for both sexes. Analyzing men and women separately revealed that diabetes and C-reactive protein seemed to be a stronger risk factors for all-cause mortality in women. Cardiovascular mortality was predicted by troponin T in women (relative risk = 5.16, 95% CI: 1.67-15.88; p = 0.004), but not in men (relative risk = 1.69; 95% CI: 0.72-3.96; p = 0.23). Our study showed for the first time that the impact of risk factors in predicting death due to cardiovascular disease is clearly gender dependent.
    Kidney and Blood Pressure Research 12/2008; 31(5):360-6. · 1.46 Impact Factor
  • Article: Kidney transplantation into urinary conduits with ureteroureterostomy between transplant and native ureter: single-center experience.
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    ABSTRACT: To evaluate the functional outcomes and complications after allogeneic kidney transplantation into recipients with a urinary conduit using ureteroureterostomy between the transplant and native ureter. We performed a retrospective study of 6 patients with a pre-existing urinary conduit undergoing kidney transplantation at a single tertiary academic center from May 1982 to February 2007. The study included 1 female and 5 males aged 16 to 65 years. Two patients received a living donor transplant. The indications for pretransplant conduit formation were neurogenic bladder in 3 and bladder contraction with vesicoureteral reflux in 3. One patient received a colon conduit. All patients underwent kidney transplantation into a urinary conduit using ureteroureterostomy between the transplant ureter and the ipsilateral native ureter. The average interval between conduit formation and kidney transplantation was 83.5 months and the average time of requiring hemodialysis was 56.3 months. The mean follow-up was 5.3 years. The patient and graft survival rate was 100% and 83.3%, respectively. The 3-year serum creatinine averaged 1.4 mg/dL. One graft was lost because of chronic rejection. Transplant ureter obstruction occurred in 2 patients and required endoscopy or open revision. Four patients underwent post-transplant native nephrectomy for recurrent pyelonephritis. Three patients were hospitalized for treatment of graft pyelonephritis. In our experience, ureteroureterostomy between the transplant and native ureter is technically feasible and provides good functional results despite a high incidence of urinary tract infection. We recommend this approach in renal transplant recipients with a short contracted conduit or in those in whom the donor ureter is too short to warrant a tension-free ureteroileal anastomosis.
    Urology 12/2008; 73(2):380-5. · 2.43 Impact Factor

Institutions

  • 2008–2012
    • Charité Universitätsmedizin Berlin
      • • Department of Nephrology
      • • Department of Urology
      Berlin, Land Berlin, Germany
  • 2011
    • Heidelberg University Hospital
      Heidelberg, Baden-Wuerttemberg, Germany
  • 2010
    • Heinrich-Heine-Universität Düsseldorf
      • Urologische Klinik
      Düsseldorf, North Rhine-Westphalia, Germany
  • 2002–2004
    • Humboldt-Universität zu Berlin
      • Department of Nephrology
      Berlin, Land Berlin, Germany