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1.
Int J Mol Sci ; 25(8)2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38673754

ABSTRACT

TIMP-2 and IGFBP7 have been identified and validated for the early detection of renal injury in critically ill patients, but data on recovery of allograft function after kidney transplantation (KTx) are scarce. In a prospective observational multicenter cohort study of renal transplant recipients, urinary [TIMP-2] × [IGFBP7] was evaluated daily from day 1 to 7 after KTx. Different stages of early graft function were defined: immediate graft function (IGF) (decrease ≥ 10% in serum creatinine (s-crea) within 24 h post KTx); slow graft function (SGF) (decrease in s-crea < 10% within 24 h post KTx); and delayed graft function (DGF) (any dialysis needed within the first week after KTx). A total of 186 patients were analyzed. [TIMP-2] × [IGFBP7] was significantly elevated as early as day 1 in patients with DGF compared to SGF and IGF. ROC analysis of [TIMP-2] × [IGFBP7] at day 1 post-transplant for event "Non-DGF" revealed a cut-off value of 0.9 (ng/mL)2/1000 with a sensitivity of 87% and a specificity of 71%. The positive predictive value for non-DGF was 93%. [TIMP-2] × [IGFBP7] measured at day 1 after KTx can predict early recovery of transplant function and is therefore a valuable biomarker for clinical decision making.


Subject(s)
Biomarkers , Insulin-Like Growth Factor Binding Proteins , Kidney Transplantation , Tissue Inhibitor of Metalloproteinase-2 , Humans , Tissue Inhibitor of Metalloproteinase-2/urine , Insulin-Like Growth Factor Binding Proteins/urine , Insulin-Like Growth Factor Binding Proteins/blood , Kidney Transplantation/adverse effects , Male , Female , Biomarkers/urine , Middle Aged , Adult , Prospective Studies , Delayed Graft Function/urine , Delayed Graft Function/diagnosis , Delayed Graft Function/etiology , ROC Curve , Aged
2.
Transpl Int ; 36: 11027, 2023.
Article in English | MEDLINE | ID: mdl-37229240

ABSTRACT

Early-on post kidney transplantation, there is a high risk of graft rejection and opportunistic viral infections. A low tacrolimus concentration/dose (C/D) ratio as a surrogate marker of fast tacrolimus metabolism has been established for risk stratification 3 months post-transplantation (M3). However, many adverse events occurring earlier might be missed, and stratification at 1 month post-transplantation (M1) has not been investigated. We retrospectively analyzed case data from 589 patients who had undergone kidney transplantation between 2011 and 2021 at three German transplant centers. Tacrolimus metabolism was estimated by use of the C/D ratio at M1, M3, M6, and M12. C/D ratios increased substantially during the year, particularly between M1 and M3. Many viral infections and most graft rejections occurred before M3. Neither at M1 nor at M3 was a low C/D ratio associated with susceptibility to BKV viremia or BKV nephritis. A low C/D ratio at M1 could not predict acute graft rejections or impaired kidney function, whereas at M3 it was significantly associated with subsequent rejections and impairment of kidney function. In summary, most rejections occur before M3, but a low C/D ratio at M1 does not identify patients at risk, limiting the predictive utility of this stratification approach.


Subject(s)
Kidney Transplantation , Tacrolimus , Humans , Tacrolimus/adverse effects , Kidney Transplantation/adverse effects , Immunosuppressive Agents/adverse effects , Retrospective Studies , Graft Rejection
3.
Int J Mol Sci ; 23(17)2022 Aug 29.
Article in English | MEDLINE | ID: mdl-36077181

ABSTRACT

The c.825C>T single-nucleotide polymorphism (rs5443) of the guanine nucleotide-binding protein subunit ß3 (GNB3) results in increased intracellular signal transduction via G-proteins. The present study investigated the effect of the GNB3 c.825C>T polymorphism on cardiovascular events among renal allograft recipients posttransplant. Our retrospective study involved 436 renal allograft recipients who were followed up for up to 8 years after transplant. The GNB3 c.825C>T polymorphism was detected with restriction fragment length polymorphism (RFLP) polymerase chain reaction (PCR). The GNB3 TT genotype was detected in 43 (10%) of 436 recipients. Death due to an acute cardiovascular event occurred more frequently among recipients with the TT genotype (4 [9%]) than among those with the CC/CT genotypes (7 [2%]; p = 0.003). The rates of myocardial infarction (MI)−free survival (p = 0.003) and acute peripheral artery occlusive disease (PAOD)−free survival (p = 0.004) were significantly lower among T-homozygous patients. A multivariate analysis showed that homozygous GNB3 c.825C>T polymorphism exerted only a mild effect for the occurrence of myocardial infarction (relative risk, 2.2; p = 0.065) or acute PAOD (relative risk, 2.4; p = 0.05) after renal transplant. Our results suggest that the homozygous GNB3 T allele exerts noticeable effects on the risk of MI and acute PAOD only in the presence of additional nonheritable risk factors.


Subject(s)
Heterotrimeric GTP-Binding Proteins , Kidney Transplantation , Myocardial Infarction , Alleles , Allografts , Genotype , Heterotrimeric GTP-Binding Proteins/genetics , Humans , Kidney Transplantation/adverse effects , Myocardial Infarction/genetics , Polymorphism, Single Nucleotide , Retrospective Studies
4.
Clin Immunol ; 226: 108698, 2021 05.
Article in English | MEDLINE | ID: mdl-33639275

ABSTRACT

T follicular helper (TFH) cells are a heterogeneous subset of immunocompetent T helper (TH) cells capable of augmenting B cell responses in lymphoid tissues. In transplantation, exposure to allogeneic tissue activates TFH cells increasing the risk of the emergence of de novo donor-specific HLA-antibodies (dnDSA). These can cause antibody-mediated rejection (AMR) and allograft loss. Follicular regulatory T (TFR) cells counteract TFH cell activity. Here, we investigated the implications of TFH and TFR cells on dnDSA formation after renal transplantation (RTX). Considering TFH cells to be CXCR5+ and IL-21+, we found by flow cytometry that patients with dnDSA produced IL-21 more abundantly compared to healthy volunteers. In in vitro alloreactivity assays, patients with dnDSA featured an enhanced alloreactive TH cell pool in response to donor-specific HLA antigens. Besides, longitudinal investigations suggested enhanced alloreactivity shortly after transplantation increasing the risk of dnDSA development. Taken together, in spite of continuous immunosuppression we report a strong IL-21 response in TFH cells and an expanded reservoir of donor-specific memory TH cells in patients with dnDSA. This warrants further investigations if aberrant TFH cell activation may precede the formation of dnDSA promoting AMR.


Subject(s)
Antibodies/immunology , Graft Rejection/immunology , Graft Survival/immunology , HLA Antigens/immunology , T-Lymphocytes, Helper-Inducer/immunology , Adult , Female , Humans , Immune Tolerance/immunology , Interleukins/immunology , Kidney Transplantation , Longitudinal Studies , Male , Middle Aged , Receptors, CXCR5/immunology
5.
Mult Scler ; 27(12): 1960-1964, 2021 10.
Article in English | MEDLINE | ID: mdl-34165361

ABSTRACT

BACKGROUND: Oral cladribine is an approved disease-modifying drug for the treatment of relapsing multiple sclerosis. In controlled clinical trials as well as in post marketing safety assessments, autoimmune conditions have not yet been reported as a specific side effect of cladribine. OBJECTIVE AND RESULTS: Here, we report a case of anti-glomerular basement membrane antibody-mediated glomerulonephritis that occurred shortly after the fourth cladribine treatment cycle. CONCLUSION: Neurologists should be attentive to the development of secondary autoimmunity in cladribine-treated patients.


Subject(s)
Glomerulonephritis , Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , Cladribine/adverse effects , Humans , Immunosuppressive Agents/adverse effects , Multiple Sclerosis/drug therapy , Multiple Sclerosis, Relapsing-Remitting/drug therapy , Neoplasm Recurrence, Local
6.
Transpl Infect Dis ; 21(5): e13146, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31306562

ABSTRACT

BACKGROUND: Transplanting kidneys from deceased donors with hepatitis C virus (HCV) viremia has been controversial for some time. Direct-acting antiviral agents have been shown to be highly effective in treating HCV infection. We report our experience with transplanting kidneys from HCV-positive donors with detectable viremia into HCV-negative recipients, followed by early treatment with a sofosbuvir-based antiviral regimen. METHODS: Data were collected from seven HCV-negative recipients receiving kidneys from five deceased HCV-viremic donors. Before transplantation, all intentional transplanted recipients had given informed consent regarding the acceptance of an HCV-viremic kidney. Recipients were closely monitored after transplant with measurements of HCV viremia, liver and renal function, and trough levels of immunosuppressive drugs. RESULTS: Four donors were infected with HCV genotype 1; the other with HCV genotype 3a. HCV viremia was detectable in all seven renal transplant recipients within 3 days after transplant. After determination of HCV genotype, antiviral treatment with a sofosbuvir-based regimen (sofosbuvir/ledipasvir, n = 4; sofosbuvir/velpatasvir, n = 3) was initiated within a median of 7 days after transplantation and was continued for 8 to 12 weeks. For all recipients, viral load was below the level of detection at the end of treatment, and all exhibited a sustained virologic response 12 weeks later. All recipients exhibited normal liver enzyme activity at the end of treatment. Renal allograft function and trough levels of tacrolimus remained stable. CONCLUSIONS: Early administration of a sofosbuvir-based regimen to HCV-negative recipients of kidneys from HCV-viremic donors is feasible and safe. The definition of an optimal therapeutic approach warrants further investigation.


Subject(s)
Antiviral Agents/administration & dosage , Hepacivirus/drug effects , Hepatitis C/prevention & control , Kidney Transplantation/adverse effects , Kidney/virology , Sofosbuvir/administration & dosage , Adult , Drug Administration Schedule , Female , Humans , Male , Middle Aged , Sustained Virologic Response , Tissue Donors , Transplant Recipients , Viral Load/drug effects , Viremia
7.
Transpl Infect Dis ; 21(3): e13088, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30929308

ABSTRACT

BACKGROUND: Hepatitis E virus (HEV) genotype 3 infection frequently progresses to chronic disease with persisting HEV viremia in immunocompromised patients. Here, we evaluated the prevalence of HEV infection in renal allograft recipients and investigated the efficacy and tolerability of ribavirin monotherapy. METHODS: A total of 947 recipients on average 8.7 years post transplant were screened for anti-HEV IgG, IgM and HEV-RNA. Sixteen HEV-viremic renal allograft recipients were treated with ribavirin for 12 weeks. HEV-RNA concentration, laboratory and clinical parameters were assessed at baseline, during therapy and 12 weeks after treatment cessation. HEV-genotyping was performed in all HEV-viremic patients. RESULTS: Past HEV infection was detected serologically in 18% of the renal allograft recipients. Ongoing HEV replication was found in 16 recipients (all genotype 3). Unanimously, distinct HEV sequences were revealed in all HEV-viremic patients. At the start of ribavirin treatment, median HEV-RNA viral load was 4.3 × 106 (8000-5.0 × 106 ) IU/mL. Ninety-four percentage of HEV-infected allograft recipients showed a sustained virological response 12 weeks after treatment cessation. Ribavirin treatment was associated with rapid decrease in liver enzymes and rare occurrence of anemia. CONCLUSIONS: Prevalence of active HEV infection is important in renal transplant patients without signs of nosocomial infection. Ribavirin treatment was safe and effective.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis Antibodies/blood , Hepatitis E/drug therapy , Kidney Transplantation , Ribavirin/therapeutic use , Adult , Aged , Allografts , Female , Genotype , Hepatitis E/epidemiology , Hepatitis E virus/genetics , Hepatitis E virus/immunology , Humans , Immunocompromised Host , Male , Middle Aged , Phylogeny , Prevalence , RNA, Viral/blood , Transplantation, Homologous , Young Adult
8.
BMC Nephrol ; 20(1): 167, 2019 05 14.
Article in English | MEDLINE | ID: mdl-31088392

ABSTRACT

BACKGROUND: The influence of pre- or postprandial administration on pharmacokinetics of cyclosporine is supposed to be less in gel-based formulations than in microemulsions. This study was designed to investigate the influence of a high-fat meal on the pharmacokinetic profile of the two cyclosporine containing formulations Ciclosporin Pro (gel-based emulsion) and Sandimmun®Optoral (microemulsion) in renal transplant recipients. METHODS: A randomized, open-label, repeated-measurement, comparative phase IV trial was conducted with two sequence groups for nutrition condition (fasting→fed, fed→fasting) and two treatment phases (Sandimmun® Optoral → Ciclosporin Pro), each covering both nutrition conditions. Primary pharmacokinetic variable of interest was the reduction of bioavailability due to high-fat food compared to fasting conditions measured by the difference D of ln-transformed bioavailability variables (AUCSS, τ, Css, max, und Css, min). RESULTS: A nutrition effect was found for both study medications with respect to the parameters AUCSS, τ and CSS, max, but not to CSS, min. The reduction of bioavailability caused by high-fat food was not significantly different for Sandimmun®Optoral and Ciclosporin Pro. CONCLUSIONS: An effect of high-fat breakfast prior to the morning dose on AUCSS, τ and CSS, max was found for Sandimmun® Optoral and for Ciclosporin Pro. Trough level monitoring did not capture ingestion-related variability. Conversion to Ciclosporin Pro seems to be safe with regard to intra-individual pharmacokinetic variability. TRIAL REGISTRATION: EudraCT No. 2009-011354-18 (29th April 2019).


Subject(s)
Cyclosporine/metabolism , Diet, High-Fat , Drug Compounding/methods , Fasting/metabolism , Immunosuppressive Agents/metabolism , Kidney Transplantation , Adult , Aged , Biological Availability , Diet, High-Fat/trends , Drug Industry/trends , Female , Humans , Kidney Transplantation/trends , Male , Middle Aged , Single-Blind Method
9.
BMC Nephrol ; 20(1): 430, 2019 11 21.
Article in English | MEDLINE | ID: mdl-31752784

ABSTRACT

BACKGROUND: Dysregulation of the B-cell activating factor (BAFF) system is involved in the pathogenesis of systemic lupus erythematosus (SLE). Increased serum concentrations of BAFF are related to lupus nephritis and disease activity among SLE patients. Recently, a variant of the BAFF-encoding gene, BAFF-var, was identified to be associated with autoimmune diseases, in particular SLE, and to promote the production of soluble BAFF. The present study aimed to assess the prevalence of BAFF-var in a cohort of 195 SLE patients and to analyze the association of the BAFF-var genotype (TNSF13B) with various manifestations of SLE. METHODS: A cohort of 195 SLE patients from Central Europe, including 153 patients from the Swiss SLE Cohort Study and 42 patients from the University Hospital Essen, Germany, underwent genotyping for detection of BAFF-var allele. RESULTS: Of the 195 patients, 18 (9.2%) tested positive for BAFF-var variant according to the minor allele frequency of 4.6%. The presence of BAFF-var was associated with the occurrence of lupus nephritis (p = 0.038) (p = 0.03 and p = 0.003). Among various organ manifestations of SLE, the presence of BAFF-var was associated with the occurrence of lupus nephritis (p = 0.038; odds ratio [OR], 2.4; 95% confidence interval [CI], 0.89-6.34) and renal activity markers such as proteinuria and hematuria (p = 0.03; OR, 2.4; 95% CI, 0.9-6.4 for proteinuria; p = 0.003; OR, 3.9; 95% CI, 1.43-10.76 for hematuria). SLE patients carrying the BAFF-var allele exhibited increased disease activity at study entry, as determined by the physician's global assessment (PGA: p = 0.002; OR, 4.8; 95% CI, 1.54-14.93) and the SLE Disease Activity Index (p = 0.012; OR, 3.5; 95% CI, 1.12-11.18). Consistent with that, the percentage of patients treated with immunosuppressive agents at study entry was higher among those carrying the BAFF-var allele than among those tested negative for BAFF-var (p = 0.006; OR, 3.7; 95% CI, 1.27-10.84). CONCLUSIONS: Our results indicate an association between the BAFF-var genotype and increased severity of SLE. Determining the BAFF-var status of SLE patients may improve the risk stratification of patients for whom the development of lupus nephritis is more likely and thus may be helpful in the follow-up care and treatment of SLE patients.


Subject(s)
Alleles , B-Cell Activating Factor/genetics , Genetic Variation , Lupus Erythematosus, Systemic/genetics , Lupus Nephritis/genetics , Adolescent , Adult , Aged , Aged, 80 and over , B-Cell Activating Factor/blood , Confidence Intervals , Female , Gene Frequency , Genetic Predisposition to Disease , Genotyping Techniques , Germany , Hematuria , Humans , Immunosuppressive Agents/therapeutic use , Lupus Erythematosus, Systemic/drug therapy , Lupus Nephritis/drug therapy , Male , Middle Aged , Odds Ratio , Proteinuria , Switzerland , Young Adult
10.
Nephrol Dial Transplant ; 33(1): 54-64, 2018 Jan 01.
Article in English | MEDLINE | ID: mdl-28992184

ABSTRACT

METHODS: Levels of serum BAFF, IgG anti-BAFF and BAFF-IgG complexes were quantified by enzyme-linked immunosorbent assay. IgG anti-BAFF and BAFF-IgG complexes were further characterized using serum fractions obtained by fast protein liquid chromatography. To study the association of serum BAFF, IgG anti-BAFF and BAFF-IgG complex levels with SLE manifestations, 373 visits from 178 patients prospectively included in the Swiss SLE Cohort Study were analysed. RESULTS: While IgG anti-BAFF levels were not associated with clinical manifestations of SLE, serum BAFF levels correlated with disease activity and were higher in patients with renal involvement. Interestingly, we could also demonstrate the occurrence of BAFF-IgG complexes of different sizes in the sera of SLE patients, which were not due to treatment with belimumab and differed from complexes constructed in vitro. Most strikingly, the levels of these BAFF-IgG complexes were found to strongly correlate with overall disease activity, low complement levels and a history of lupus nephritis. CONCLUSION: BAFF-IgG complexes strongly correlate with disease activity in SLE patients, suggesting a pathogenic role in SLE.


Subject(s)
Antibodies, Anti-Idiotypic/blood , Antigen-Antibody Complex/blood , Autoantibodies/blood , B-Cell Activating Factor/blood , Immunoglobulin G/blood , Lupus Erythematosus, Systemic/blood , Lupus Erythematosus, Systemic/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Anti-Idiotypic/immunology , Antigen-Antibody Complex/immunology , Autoantibodies/immunology , B-Cell Activating Factor/immunology , Female , Humans , Immunoglobulin G/immunology , Lupus Erythematosus, Systemic/immunology , Male , Middle Aged , Prospective Studies , Young Adult
11.
BMC Nephrol ; 19(1): 154, 2018 06 28.
Article in English | MEDLINE | ID: mdl-29954336

ABSTRACT

BACKGROUND: Conversion from calcineurin inhibitor (CNI) therapy to everolimus within 6 months after kidney transplantation improves long-term graft function but can increase the risk of mild biopsy-proven acute cellular rejection (BPAR). We performed a post-hoc analysis of histological data from a randomized trial in order to further analyze histologic information obtained from indication and protocol biopsies up to 5 years after transplantation. METHODS: Biopsy samples obtained up to 5 years post-transplant were analyzed from the randomized ZEUS study, in which kidney transplant patients were randomized at month 4.5 to switch to everolimus (n = 154) or remain on cyclosporine (CsA)-based immunosuppression (n = 146). All patients received mycophenolate and steroids. RESULTS: At least one investigator-initiated biopsy was undertaken in 53 patients in each group between randomization and year 5, with a mean (SD) of 2.6 (1.7) and 2.2 (1.4) biopsies per patient in the everolimus and CsA groups, respectively. In the everolimus and CsA groups, investigator-initiated biopsies showed (i) BPAR in 12.3 and 7.5% (p = 0.182) of patients, respectively, with episodes graded mild in 22/24 and 18/20 cases (ii) CsA toxicity lesions in 4.5 and 10.3% of patients (p = 0.076) (iii) antibody-mediated rejection in 0.6 and 2.7% of patients (p = 0.204), respectively. CONCLUSIONS: This analysis of histological findings in the ZEUS study to 5 years after kidney transplantation shows no increase in antibody-mediated rejection under everolimus-based therapy with a lower rate of CNI-related toxicity compared to a conventional CsA-based regimen, and confirms the preponderance of mild BPAR seen in the main study after the early switch to CsA-free everolimus therapy. TRIAL REGISTRATION: ClinicalTrials.gov NCT00154310 . Date of registration: September 12, 2005.


Subject(s)
Cyclosporine/administration & dosage , Drug Substitution/trends , Everolimus/administration & dosage , Graft Survival/drug effects , Immunosuppressive Agents/administration & dosage , Kidney Transplantation/trends , Adolescent , Adult , Aged , Drug Substitution/methods , Female , Graft Survival/physiology , Humans , Male , Middle Aged , Time Factors , Young Adult
12.
BMC Nephrol ; 19(1): 237, 2018 09 19.
Article in English | MEDLINE | ID: mdl-30231851

ABSTRACT

BACKGROUND: Conversion from calcineurin inhibitor (CNI) therapy to a mammalian target of rapamycin (mTOR) inhibitor following kidney transplantation may help to preserve graft function. Data are sparse, however, concerning the impact of conversion on posttransplant diabetes mellitus (PTDM) or the progression of pre-existing diabetes. METHODS: PTDM and other diabetes-related parameters were assessed post hoc in two large open-label multicenter trials. Kidney transplant recipients were randomized (i) at month 4.5 to switch to everolimus or remain on a standard cyclosporine (CsA)-based regimen (ZEUS, n = 300), or (ii) at month 3 to switch to everolimus, remain on standard CNI therapy or convert to everolimus with reduced-exposure CsA (HERAKLES, n = 497). RESULTS: There were no significant differences in the incidence of PTDM between treatment groups (log rank p = 0.97 [ZEUS], p = 0.90 [HERAKLES]). The mean change in random blood glucose from randomization to month 12 was also similar between treatment groups in both trials for patients with or without PTDM, and with or without pre-existing diabetes. The change in eGFR from randomization to month 12 showed a benefit for everolimus versus comparator groups in all subpopulations, but only reached significance in larger subgroups (no PTDM or no pre-existing diabetes). CONCLUSIONS: Within the restrictions of this post hoc analysis, including non-standardized diagnostic criteria and limited glycemia laboratory parameters, these data do not indicate any difference in the incidence or severity of PTDM with early conversion from a CsA-based regimen to everolimus, or in the progression of pre-existing diabetes. TRIAL REGISTRATION: clinicaltrials.gov , NCT00154310 (registered September 2005) and NCT00514514 (registered August 2007); EudraCT ( 2006-007021-32 and 2004-004346-40 ).


Subject(s)
Cyclosporine/administration & dosage , Diabetes Mellitus/epidemiology , Everolimus/administration & dosage , Kidney Transplantation/trends , Multicenter Studies as Topic/methods , Randomized Controlled Trials as Topic/methods , Aged , Cyclosporine/adverse effects , Diabetes Mellitus/chemically induced , Diabetes Mellitus/diagnosis , Disease Progression , Everolimus/adverse effects , Female , Graft Rejection/diagnosis , Graft Rejection/epidemiology , Graft Rejection/prevention & control , Humans , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/adverse effects , Kidney Transplantation/adverse effects , Male
13.
Nephrol Dial Transplant ; 32(5): 880-889, 2017 May 01.
Article in English | MEDLINE | ID: mdl-28340245

ABSTRACT

BACKGROUND: The assignment of human leucocyte antigens (HLAs) against which antibodies are detected as unacceptable antigens (UAGs) avoids allocation of HLA- incompatible allografts. There is uncertainty as to what extent UAGs decrease the probability of receiving a kidney offer. METHODS: Kidney transplantations in 3264 patients on the waiting lists of six German transplant centres were evaluated for a period of at least 2 years. The proportion of excluded offers due to UAGs was calculated as virtual panel-reactive antibodies (vPRAs). RESULTS: In the common Eurotransplant Kidney Allocation Scheme, the transplant probability was unaffected by vPRAs in exploratory univariate analyses. In the multivariable model, a 1% increase in vPRA values was outweighed by an additional waiting time of 2.5 weeks. The model was confirmed using an external validation cohort of 1521 patients from seven centres. If only patients with standard risk were considered (e.g. no simultaneous transplantation of other organs), only 1.3 weeks additional waiting time was needed. In the Eurotransplant Senior Program, patients with vPRA values >50% had a strongly reduced transplant probability in the unadjusted analyses. In the multivariable model, a 1% increase in vPRA values was outweighed by an additional waiting time of 5 weeks. CONCLUSIONS: This study demonstrates that the assignment of UAGs decreases the transplant probability in both main Eurotransplant allocation programs because of insufficient compensatory mechanisms. At present, for immunized patients, a prolonged waiting time has to be weighed against the increased immunologic risk due to donor-specific antibodies not assigned as UAGs.


Subject(s)
HLA Antigens/immunology , Kidney Failure, Chronic/surgery , Kidney Transplantation/statistics & numerical data , Kidney/immunology , Tissue Donors , Tissue and Organ Procurement/methods , Waiting Lists , Adult , Aged , Female , Histocompatibility Testing , Humans , Male , Middle Aged , Retrospective Studies , Transplantation, Homologous
14.
Transpl Int ; 30(12): 1226-1233, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28574620

ABSTRACT

Nonaccepted kidneys grafts enter the rescue allocation (RA) process to avoid discards. In December 2013, recipient oriented extended allocation (REAL) was introduced to improve transparency. The aim of this study was to evaluate the influence of REAL on recipients' selection and graft function compared to the formerly existing RA as well as to identify factors that influence graft outcome. Therefore, a multicenter study of 10 transplant centers in the same region in Germany was performed. All transplantations after RA or REAL from December 1, 2012, until December 31, 2014, with a follow-up time until December 31, 2015 were analyzed. 113 of 941 kidney transplantations were performed after RA or REAL (12%). With REAL, the number of refusals before transplantation had increased (12 ± 7.1 vs. 8.6 ± 8.6, P = 0.036), and cold ischemia time has decreased (13.6 ± 3.6 vs. 17.2 ± 4.8 h, P = 0.019). Recipients after REAL needed significantly more allocation points compared to RA to receive a kidney. One-year graft survival was comparable. If kidneys from the same donor were transplanted to two recipients at one center, the greater the difference in recipient age, the greater the difference in serum creatinine after 12 months (-0.019 mg/dl per year, P = 0.011) was, that is older recipients showed lower creatinine. REAL influences selection of the recipients compared to the former RA era for successful organ receipt. Graft function is comparable and seems to be influenced by recipient age.


Subject(s)
Donor Selection/methods , Kidney Transplantation/methods , Tissue and Organ Procurement/methods , Transplant Recipients , Adult , Age Factors , Aged , Cohort Studies , Female , Germany , Graft Rejection , Graft Survival , Humans , Kaplan-Meier Estimate , Kidney Transplantation/adverse effects , Kidney Transplantation/mortality , Male , Middle Aged , Retrospective Studies , Risk Assessment , Statistics, Nonparametric , Survival Analysis , Time Factors , Treatment Outcome
15.
J Am Soc Nephrol ; 27(1): 239-48, 2016 Jan.
Article in English | MEDLINE | ID: mdl-25925688

ABSTRACT

Calciprotein particle maturation time (T50) in serum is a novel measure of individual blood calcification propensity. To determine the clinical relevance of T50 in renal transplantation, baseline serum T50 was measured in a longitudinal cohort of 699 stable renal transplant recipients and the associations of T50 with mortality and graft failure were analyzed over a median follow-up of 3.1 years. Predictive value of T50 was assessed for patient survival with reference to traditional (Framingham) risk factors and the calcium-phosphate product. Serum magnesium, bicarbonate, albumin, and phosphate levels were the main determinants of T50, which was independent of renal function and dialysis vintage before transplant. During follow-up, 81 (12%) patients died, of which 38 (47%) died from cardiovascular causes. Furthermore, 45 (6%) patients developed graft failure. In fully adjusted models, lower T50 values were independently associated with increased all-cause mortality (hazard ratio, 1.43; 95% confidence interval, 1.11 to 1.85; P=0.006 per SD decrease) and increased cardiovascular mortality (hazard ratio, 1.55; 95% confidence interval, 1.04 to 2.29; P=0.03 per SD decrease). In addition to age, sex, and eGFR, T50 improved prognostication for all-cause mortality, whereas traditional risk factors or calcium-phosphate product did not. Lower T50 was also associated with increased graft failure risk. The associations of T50 with mortality and graft failure were confirmed in an independent replication cohort. In conclusion, reduced serum T50 was associated with increased risk of all-cause mortality, cardiovascular mortality, and graft failure and, of all tested parameters, displayed the strongest association with all-cause mortality in these transplant recipients.


Subject(s)
Calcinosis/mortality , Kidney Transplantation , Postoperative Complications/mortality , Calcinosis/blood , Calcinosis/epidemiology , Calcium Pyrophosphate/blood , Female , Humans , Male , Middle Aged , Postoperative Complications/blood , Postoperative Complications/epidemiology , Predictive Value of Tests , Prospective Studies , Risk Factors , Survival Rate
16.
Radiology ; 279(3): 795-804, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26744926

ABSTRACT

Purpose To determine renal oxygenation changes associated with uninephrectomy and transplantation in both native donor kidneys and transplanted kidneys by using blood oxygenation level-dependent (BOLD) MR imaging. Materials and Methods The study protocol was approved by the local ethics committee. Thirteen healthy kidney donors and their corresponding recipients underwent kidney BOLD MR imaging with a 3-T imager. Written informed consent was obtained from each subject. BOLD MR imaging was performed in donors before uninephrectomy and in donors and recipients 8 days, 3 months, and 12 months after transplantation. R2* values, which are inversely related to tissue partial pressure of oxygen, were determined in the cortex and medulla. Longitudinal R2* changes were statistically analyzed by using repeated measures one-way analysis of variance with post hoc pair-wise comparisons. Results R2* values in the remaining kidneys significantly decreased early after uninephrectomy in both the medulla and cortex (P < .003), from 28.9 sec(-1) ± 2.3 to 26.4 sec(-1) ± 2.5 in the medulla and from 18.3 sec(-1) ± 1.5 to 16.3 sec(-1) ± 1.0 in the cortex, indicating increased oxygen content. In donors, R2* remained significantly decreased in both the medulla and cortex at 3 (P < .01) and 12 (P < .01) months. In transplanted kidneys, R2* remained stable during the first year after transplantation, with no significant change. Among donors, cortical R2* was found to be negatively correlated with estimated glomerular filtration rate (R = -0.47, P < .001). Conclusion The results suggest that BOLD MR imaging may potentially be used to monitor renal functional changes in both remaining and corresponding transplanted kidneys. (©) RSNA, 2016.


Subject(s)
Kidney Transplantation , Kidney/blood supply , Magnetic Resonance Imaging/methods , Oxygen/blood , Female , Follow-Up Studies , Humans , Kidney/diagnostic imaging , Living Donors , Longitudinal Studies , Male , Middle Aged , Nephrectomy , Organ Size , Tissue Donors
17.
Clin Nephrol ; 85(4): 215-25, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26932178

ABSTRACT

AIMS: To assess 5-year efficacy, renal, and safety outcomes following early conversion from cyclosporine to everolimus vs. a standard cyclosporine-based regimen in living-donor kidney transplant (LDKT) recipients. MATERIALS AND METHODS: The ZEUS study was a randomized, open-label, 1-year, multicenter study in which 300 de novo kidney transplant recipients continued to receive cyclosporine or converted to everolimus at 4.5 months post-transplant, with annual follow-up visits to 5 years post-transplant. RESULTS: Of the 80 LDKT patients who were randomized, 75 completed the 1-year core study and 60 attended the 5-year follow-up visit. At year 5, 15/31 (48.4%) everolimus patients and 20/29 (69.0%) cyclosporine patients remained on the study drug. Mean adjusted estimated glomerular filtration rate (GFR) at year 5 in LDKT recipients was 67.2 vs. 60.8 mL/min/1.73m2 for everolimus vs. cyclosporine (mean difference 6.4 mL/min/1.73m2; p = 0.031). For patients who remained on study drug, the mean difference was 13.2 mL/min/1.73m2 (p = 0.003), but no significant difference was seen in patients who switched from study drug (mean -2.6 mL/min/1.73m2, p = 0.701). Patient and graft survival rates were similar with everolimus and cyclosporine. Biopsy-proven acute rejection occurred in 22.0% vs. 7.5% of LDKT patients randomized to everolimus vs. cyclosporine (p = 0.116). Only 1 LDKT patient discontinued everolimus due to adverse events during years 1 - 5. CONCLUSIONS: Early initiation of everolimus with calcineurin-inhibitor (CNI) withdrawal after LDKT improved graft function to 5 years post-transplant compared to standard CNI-based therapy. The renal benefit was concentrated in patients who remained on everolimus. An increase in mild acute rejection was not associated with long-term graft loss.


Subject(s)
Cyclosporine/therapeutic use , Everolimus/therapeutic use , Immunosuppressive Agents/therapeutic use , Kidney Transplantation/methods , Living Donors , Adult , Calcineurin Inhibitors/therapeutic use , Cohort Studies , Female , Follow-Up Studies , Glomerular Filtration Rate/drug effects , Graft Rejection/diagnosis , Graft Survival , Humans , Intention to Treat Analysis , Male , Middle Aged , Proteinuria/urine , Safety , Survival Rate , Treatment Outcome
19.
Radiology ; 270(3): 800-8, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24475796

ABSTRACT

PURPOSE: To determine whether diffusion-weighted (DW) magnetic resonance (MR) imaging in living renal allograft donation allows monitoring of potential changes in the nontransplanted remaining kidney of the donor because of unilateral nephrectomy and changes in the transplanted kidney before and after transplantation in donor and recipient, respectively, and whether DW MR parameters are correlated in the same kidney before and after transplantation. MATERIALS AND METHODS: The study protocol was approved by the local ethics committee; written informed consent was obtained. Thirteen healthy kidney donors and their corresponding recipients prospectively underwent DW MR imaging (multiple b values) in donors before donation and in donors and recipients at day 8 and months 3 and 12 after donation. Total apparent diffusion coefficient (ADCT) values were determined; contribution of microcirculation was quantified in perfusion fraction (FP). Longitudinal changes of diffusion parameters were compared (repeated-measures one-way analysis of variance with post hoc pairwise comparisons). Correlations were tested (linear regression). RESULTS: ADCT values in nontransplanted kidney of donors increased from a preexplantation value of (188 ± 9 [standard deviation]) to (202 ± 11) × 10(-5) mm(2)/sec in medulla and from (199 ± 11) to (210 ± 13) × 10(-5) mm(2)/sec in cortex 1 week after donation (P < .004). Medullary, but not cortical, ADCT values stayed increased up to 1 year. ADCT values in allografts in recipients were stable. Compared with values obtained before transplantation in donors, the corticomedullary difference was reduced in allografts (P < .03). Cortical ADCT values correlated with estimated glomerular filtration rate in recipients (R = 0.56, P < .001) but not donors. Cortical ADCT values in the same kidney before transplantation in donors correlated with those in recipients on day 8 after transplantation (R = 0.77, P = .006). FP did not show significant changes. CONCLUSION: DW MR imaging depicts early adaptations in the remaining nontransplanted kidney of donors after nephrectomy. All diffusion parameters remained constant in allograft recipients after transplantation. This method has potential monitoring utility, although assessment of clinical relevance is needed.


Subject(s)
Diffusion Magnetic Resonance Imaging , Kidney Transplantation , Living Donors , Adult , Aged , Allografts , Female , Follow-Up Studies , Humans , Immunosuppressive Agents/therapeutic use , Longitudinal Studies , Male , Microcirculation , Middle Aged , Nephrectomy , Prospective Studies , Treatment Outcome
20.
Transpl Int ; 27(11): 1192-204, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25070687

ABSTRACT

Conversion of living-donor kidney transplant patients from calcineurin inhibitor therapy to an mTOR inhibitor is poorly documented. In the prospective, multicentre ZEUS study, 300 kidney transplant recipients without prior rejection (Banff grade >1) and serum creatinine ≤265 µmol/l were randomized to continue cyclosporine or convert to everolimus at 4.5 months post-transplant. In a post hoc analysis of 80 living-donor recipients, adjusted estimated GFR (Nankivell) at month 12 (the primary endpoint) was 74.3 (95% CI [70.7, 77.9]) ml/min/1.73 m(2) with everolimus versus 63.8 (95% CI [60.0, 67.7]) ml/min/1.73 m(2) ) with cyclosporine, a difference of 10.5 ml/min/1.73 m(2) in favour of everolimus (P < 0.001). From randomization to month 12, adjusted estimated GFR increased by a mean of 9.8 (95% CI [6.2, 13.4]) ml/min/1.73 m(2) with everolimus versus -0.7 (95% CI [-4.6, 3.1]) ml/min/1.73 m(2) ) (P < 0.001) with cyclosporine. There were six biopsy-proven acute rejection episodes in everolimus-treated patients (five Banff grade I) and one episode in cyclosporine-treated patients (Banff grade 1). Overall safety profile was similar between groups. Discontinuation due to adverse events occurred in three everolimus patients (7.1%) and five cyclosporine patients (13.2%) between randomization and month 12. Initiation of everolimus with early elimination of calcineurin therapy is associated with a significant renal benefit at 12 months post-transplant that is observed in both living and deceased-donor recipients. (clinicaltrials.gov NCT00154310).


Subject(s)
Cyclosporine/administration & dosage , Immunosuppressive Agents/administration & dosage , Kidney Transplantation , Sirolimus/analogs & derivatives , Adult , Calcineurin Inhibitors/administration & dosage , Calcineurin Inhibitors/adverse effects , Cohort Studies , Cyclosporine/adverse effects , Drug Administration Schedule , Everolimus , Female , Glomerular Filtration Rate , Humans , Immunosuppressive Agents/adverse effects , Living Donors , Male , Middle Aged , Prospective Studies , Sirolimus/administration & dosage , Sirolimus/adverse effects , TOR Serine-Threonine Kinases/antagonists & inhibitors , Transplant Recipients , Treatment Outcome
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