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Many transplant physicians screen for and treat asymptomatic bacteriuria (ASB) during post-kidney-transplant surveillance. We investigated whether antibiotics are effective in reducing the occurrence of symptomatic urinary tract infection (UTI) in kidney transplant recipients with ASB., info:eu-repo/semantics/published

Summary In the 1960s, our predecessors won a historical battle against acute rejection and ensured that transplantation became a common life-saving treatment. In parallel with this success, or perhaps because of it, we lost the battle for long-lived transplants, being overwhelmed with chronic immune insults and the toxicities of immunosuppression. It is likely that current powerful treatments block acute rejection, but at the same time condemn the few circulating donor cells that would have been able to elicit immunoregulatory host responses towards the allograft. Under these conditions, spontaneously tolerant kidney recipients – i.e. patients who maintain allograft function in the absence of immunosuppression – are merely accidents; they are scarce, mysterious and precious. Several teams pursue the goal of finding a biomarker that would guide us towards the ‘just right’ level of immunosuppression that avoids rejection while leaving some space for donor immune cells. Some cellular assays are attractive because they are antigen-specific, and provide a comprehensive view of immune responses toward the graft. These seem to closely follow patient regulatory capacities. However, these tests are cumbersome, and require abundant cellular material from both donor and recipient. The latest newcomers, non-antigen-specific recipient blood transcriptomic biomarkers, offer the promise that a practicable and simple signature may be found that overcomes the complexity of a system in which an infinite number of individual cell combinations can lead possibly to graft acceptance. Biomarker studies are as much an objective – identifying tolerant patients, enabling tolerance trials – as a means to deciphering the underlying mechanisms of one of the most important current issues in transplantation.

Acute renal rejection is a major risk factor for chronic allograft dysfunction and long-term graft loss. We performed a genome-wide association study to detect loci associated with biopsy-proven acute T cell-mediated rejection occurring in the first year after renal transplantation. In a discovery cohort of 4127 European renal allograft recipients transplanted in eight European centers, we used a DNA pooling approach to compare 275 cases and 503 controls, on Illumina 2·5 M arrays. In an independent replication cohort of 2765 patients transplanted in two European countries, we identified 313 cases and 531 controls, in whom we genotyped individually the most significant SNPs from the discovery cohort. In the discovery cohort, we found 5 candidate loci tagged by a number of contiguous SNPs (>5) that was never reached in iterative in silico permutations of our experimental data. In the replication cohort, two loci remained significantly associated with acute rejection in both univariate and multivariate analysis. One locus encompasses PTPRO, coding for a receptor-type tyrosine kinase essential for B cell receptor signalling. The other locus involves ciliary gene CCDC67, in line with the emerging concept of a shared building design between the immune synapse and the primary cilium. This article is protected by copyright. All rights reserved., FLWOA, SCOPUS: ar.j, info:eu-repo/semantics/published

BACKGROUND: Shipment of organs during the allocation process aims to improve human leucocyte antigen (HLA) matching but can also have a detrimental effect by prolonging cold ischaemia. The overall effect of organ exchange on post-transplant outcomes in the Eurotransplant (ET) region has not been investigated. METHODS: This is a retrospective single-centre cohort study to investigate the effect of shipment of renal allografts on cold ischaemia times and the incidence of acute rejection (AR) and graft survival in 661 transplantations of deceased donor kidneys. RESULTS: Forty-six per cent (N = 301) of the patients received a locally procured and 54% (N = 360) a shipped donor kidney. Locally procured donors tended to be older, more often hypertensive and had less frequently died from trauma. Recipients of shipped kidneys were at higher immunological risk, being younger, more frequently retransplanted and immunized against HLA antigens. Shipped kidneys had a 2.2-h prolongation of cold ischaemia time (18.0 versus 20.2 h; P < 0.0001) but significantly less HLA A, B and DR mismatches (2.20 versus 2.84; P < 0.0001). Recipients of shipped kidneys had an increased incidence of first-year AR [19 versus 13%; odds ratio 1.62 (1.06-2.49); P = 0.026] and death-censored graft loss [hazard ratio 1.6 (1.1-2.4); P = 0.01] that was no longer statistically significant after adjustments for risk factors by multivariable modelling. CONCLUSIONS: Shipment of kidneys in the ET region is associated with a modest increase in cold ischaemia time and significantly better HLA matching. This allows for successful transplantation of higher risk patients with no significant penalty with regard to AR rates or death-censored graft survival.

Background. Several studies suggest that the introduction of tacrolimus (TRL), mycophenolic acid (MPA) and interleukin 2 receptor antibodies (IL2Ra) as single drugs more than a decade ago has not increased the risk of malignancy after renal transplantation. However, only limited data are available on their carcinogenic effects when used in combination as a potent immunosuppressive regimen. Methods. A retrospective single-centre cohort study on 929 adult renal transplant recipients. Investigation of the effect of two consecutive immunosuppressive regimens [1993–98, N ¼ 405, anti-lymphocyte antibodies, cyclosporine and azathioprine (AZA); 1999–2007, N ¼ 524, predominantly IL2Ra, TRL and MPA] on the incidence rate of skin cancer, solid tumours and post-transplant lymphoproliferative disease (PTLD). Results. In total, 365 malignancies developed among 113 patients. As compared to the previous cyclosporine and AZA-based immunosuppression, the introduction of the new immunosuppressive regimen did not increase the incidence rate of skin cancer [rate ratio 0.84; 95% confidence interval (CI) 0.48–1.46], solid tumours (0.89; 95% CI 0.46–1.67) and PTLD (0.82; 95% CI 0.28–2.21). Patients treated with the more recent regimens less frequently developed multiple skin cancers and invasive squamous cell cancer. Skin cancer after transplantation was strongly associated with the development of solid tumours (odds ratio 5.2; P < 0.0001). The introduction of the new immunosuppressive drugs reduced the incidence of first year acute rejection from 34.8 to 13.2% (P < 0.0001). Conclusion. Although significantly more efficient in the prevention of acute rejection, the introduction of TRL, MPA and IL2Ra-based immunosuppression after kidney transplantation was not associated with an increased incidence of skin cancer, solid tumours or PTLD.

Kianda MN, Wissing KM, Broeders NE, Lemy A, Ghisdal L, Hoang AD, Mikhalski D, Donckier V, Vereerstraeten P, Abramowicz D. Ineligibility for renal transplantation: prevalence, causes and survival in a consecutive cohort of 445 patients. Clin Transplant 2011: 25: 576–583. © 2010 John Wiley & Sons A/S. Abstract: Little is known about the proportion of renal transplant candidates who are considered ineligible by the transplant center, the reasons of their ineligibility and their survival during dialysis. In this retrospective, single-center study of 445 adult patients referred between 2001 and 2006, 36 (8%) were deemed ineligible for medical contraindications. The leading reason was cardiovascular (CV) (75%), specifically aorto-iliac, and/or limb vessels atheromatosis or calcifications; ischemic heart disease; or a combination thereof. Nine patients had other contraindications that were absolute for three of them; six patients displayed a combination of relative contraindications. When compared to eligible patients (N = 409), those ineligible were significantly older (60 yr vs. 48), more often diabetics (50% vs. 15%), obese (39% vs. 17%) suffering from coronary artery disease (53% vs. 11%) and peripheral arterial disease (86% vs. 11%). Their primary nephropathy was more often diabetic and/or hypertensive/nephroangiosclerosis (61% vs. 23%), and their median dialysis vintage prior to evaluation was longer (29 months vs. 10, p

Summary Renal allograft biopsies ( n = 34) of two different populations of patients according to the immunological risk (high versus low-risk) have been compared retrospectively. The presence of polymorphonuclear leukocytes in peritubular capillaries was more frequent in the high-risk group. The C4d staining was positive in 10% of the low-risk patients and in 50% of the high-risk patients ( P = 0.03). There were more early graft loss, renal infarctions, interstitial hemorrhage, severe glomerulitis, neutrophilic glomerulitis and Banff III grade rejection in the positive C4d group. In conclusion, half of the immunized patients had a humoral rejection, patients with a C4d positive rejection had more early graft loss and more severe histological lesions.

The role of the anti-apoptotic protein Bcl-2 in lung cancer remains controversial. In order to clarify its impact on survival in small and non-small cell lung cancer (NSCLC), we performed a systematic review of the literature. Trials were selected for further analysis if they provided an independent assessment of Bcl-2 in lung cancer and reported analysis of survival data according to Bcl-2 status. To make it possible to aggregate survival results of the published studies, their methodology was assessed using a quality scale designed by the European Lung Cancer Working Party (including study design, laboratory methods and analysis). Of 28 studies, 11 identified Bcl-2 expression as a favourable prognostic factor and three linked it with poor prognosis; 14 trials were not significant. No differences in scoring measurement were detected between the studies, except that significantly higher scores were found in the trials with the largest sample sizes. Assessments of methodology and of laboratory technique were made independently of the conclusion of the trials. A total of 25 trials, comprising 3370 patients, provided sufficient information for the meta-analysis. The studies were categorised according to histology, disease stage and laboratory technique. The combined hazard ratio (HR) suggested that a positive Bcl-2 status has a favourable impact on survival: 0.70 (95% confidence interval 0.57-0.86) in seven studies on stages I-II NSCLC; 0.50 (0.39-0.65) in eight studies on surgically resected NSCLC; 0.91 (0.76-1.10) in six studies on any stage NSCLC; 0.57 (0.41-0.78) in five studies on squamous cell cancer; 0.75 (0.61-0.93) and 0.71 (0.61-0.83) respectively for five studies detecting Bcl-2 by immunohistochemistry with Ab clone 100 and for 13 studies assessing Bcl-2 with Ab clone 124; 0.92 (0.73-1.16) for four studies on small cell lung cancer; 1.26 (0.58-2.72) for three studies on neuroendocrine tumours. In NSCLC, Bcl-2 expression was associated with a better prognosis. The data on Bcl-2 expression in small cell lung cancer were insufficient to assess its prognostic value., Journal Article, Meta-Analysis, Research Support, Non-U.S. Gov't, Review, info:eu-repo/semantics/published

BACKGROUND: Patients undergoing kidney transplantation are sometimes being treated with antiplatelet agents such as ticlopidine or clopidogrel. Some teams refuse to wait-list these patients for fear of bleeding during transplant surgery. METHODS: We retrospectively reviewed the records of 702 adult patients with a kidney transplant alone between 2000 and 2010. Nineteen (2.7%) patients were taking clopidogrel or ticlopidine when called in for transplantation. Furthermore, 10 of these 19 patients were also taking low-dose aspirin (ASA). We compared the risk of bleeding peri- and postoperatively, and the occurrence of cardiovascular complications within 30 days after renal transplantation between 19 cases and 39 controls randomly selected within the cohort. RESULTS: Platelets were administered to 7 cases (37%) versus 0 controls (P

Little is known about the proportion of renal transplant candidates who are considered ineligible by the transplant center, the reasons of their ineligibility and their survival during dialysis. In this retrospective, single-center study of 445 adult patients referred between 2001 and 2006, 36 (8%) were deemed ineligible for medical contraindications. The leading reason was cardiovascular (CV) (75%), specifically aorto-iliac, and/or limb vessels atheromatosis or calcifications; ischemic heart disease; or a combination thereof. Nine patients had other contraindications that were absolute for three of them; six patients displayed a combination of relative contraindications. When compared to eligible patients (N = 409), those ineligible were significantly older (60 yr vs. 48), more often diabetics (50% vs. 15%), obese (39% vs. 17%) suffering from coronary artery disease (53% vs. 11%) and peripheral arterial disease (86% vs. 11%). Their primary nephropathy was more often diabetic and/or hypertensive/nephroangiosclerosis (61% vs. 23%), and their median dialysis vintage prior to evaluation was longer (29 months vs. 10, p0.0001). The actuarial survival of ineligible patients was significantly lower than that of eligible patients (at five yr: 53% vs. 88%). Adequate control of CV risk factors before dialysis and early referral for transplantation might help to improve eligibility of renal transplant candidates.

BACKGROUND.: Major histocompatibility complex class 1 chain-related antigen A (MICA) antibodies (Abs) have been associated with renal graft loss in one large cohort. The triggering factors for MICA Abs and their autologous or allogeneic specificity have not been well defined. More data on the impact of MICA on renal grafts outcome are needed. METHODS.: We tested sera from 494 controls and 597 patients with chronic kidney disease (CKD) for MICA using Luminex. Forty CKD MICA+ patients were genotyped for MICA alleles to determine their auto-or allospecificity. We compared MICA+ with MICA-renal transplant recipients with regard to acute rejection episodes and long-term survival. RESULTS.: Blood transfusions, previous transplantation, and more than two pregnancies were independent risk factors for the presence of MICA Abs, as were CKD stage V status and male gender. Among the 40 genotyped patients, allo-Abs alone were present in 32 patients, both auto-and allo-Abs in 4 patients, and auto-Abs alone in 4 patients. When we compared MICA+ with MICA-patients, the incidence of acute rejection episodes during the first year (10.2% vs. 12.8%), as well as 1-year creatinine and proteinuria, were similar in both groups. At 10 years, actuarial patient (97.8% vs. 87.6%) and overall graft survival (76% vs. 72%) were similar between MICA+ and MICA-patients. CONCLUSIONS.: In summary, (1) sensitizing events for MICA Abs are the same as for human leukocyte antigen Abs; (2) MICA Abs did not adversely affect renal graft outcomes in our cohort. © 2010 by Lippincott Williams & Wilkins.

International audience; New-onset diabetes after transplantation (NODAT) is a serious and frequent complication in transplant recipients. Whether NODAT shares the same susceptibility genes as type 2 diabetes is unknown. In this multicenter study, we genotyped 1076 white patients without diabetes at transplantation for 11 polymorphisms that associate with type 2 diabetes. We defined NODAT as a fasting plasma glucose > or =126 mg/dl on at least two occasions or de novo hypoglycemic therapy. We compared clinical and genetic factors between patients who developed NODAT within 6 mo of transplantation (n = 118; incidence 11%) and patients without diabetes (n = 958). In multivariate analysis, NODAT significantly associated with the following characteristics: TCF7L2 polymorphism (odds ratio [OR] 1.60 per each T allele; P = 0.002), age (OR 1.03 per year; P < 0.001), body mass index at transplantation (OR 1.09 per unit; P < 0.001), tacrolimus use (OR 2.26; P < 0.001), and the occurrence of a corticoid-treated acute rejection episode (OR 2.78; P < 0.001). In summary, our data show that the TCF7L2 rs7903146 polymorphism, a known risk factor for type 2 diabetes in the general population, also associates with NODAT.

A cohort of recipients of renal transplant after 2000 (N=310) was prospectively screened on the day of transplantation and 1 month later for a panel of 11 thrombophilic factors to assess their effect on posttransplant outcomes. All patients received prophylactic acetylsalicylic acid, started before transplantation. The rate of thromboembolic events or acute rejection episodes during the first posttransplant year (primary composite endpoint) was 16.7% among patients free of thrombophilic factor (N=60) and 17.2% in those with >or=1 thrombophilic factor (N=250) (p>0.99). The incidence of the primary endpoint was similar among patients free of thrombophilic factors and those with >or=2 (N=135), or >or=3 (N=53) factors (16.3% and 15.1% respectively; p=1) and in patients who remained thrombophilic at 1 month (15.7%; p=0.84). None of the individual thrombophilic factor present at the day of transplantation was associated with the primary endpoint. The incidence of cardiovascular events at 1-year, serum creatinine at 1-year, 4-year actuarial graft and patient survival were not influenced by the presence of >or=1 thrombophilic factor at baseline (p=NS). In conclusion, the presence of thrombophilic factors does not influence thromboembolic events, acute rejection, graft or patient survival in patients transplanted after 2000 and receiving prophylactic acetylsalicylic acid.

We retrospectively reviewed our experience with 45 kidney transplant recipients (KTR) that were switched from CNI to SRL, mainly for chronic allograft dysfunction (CAD) (41/45). The mean serum creatinine at switch was 2.5 +/- 0.8 mg/dl. At 1 year, patient survival was 93%. Death-censored graft survival was 67% at 1 year and 54% at 2 years. SRL was stopped because of severe side effects in 15 patients. Among these, eight patients developed 'de novo' high-grade proteinuria. Univariate analysis revealed that (1) a higher SRL level at 1 month was a predictor of SRL withdrawal due to severe side effects (P = 0.006), and (2) predictors of graft failure after SRL conversion were low SRL loading dose (P = 0.03) and a higher creatinine level at conversion (P = 0.003). In conclusion, the therapeutic index of SRL in patients suffering from CAD is narrow, with high exposure triggering serious adverse events that may mandate SRL discontinuation, while too low exposure may expose patients to under-immunosuppression and graft loss., Journal Article, info:eu-repo/semantics/published

Background The aim of our study was to examine, in a recent cohort of kidney transplant recipients who have received modern immunosuppressive therapy, the respective role of cold ischemia time (CIT) and delayed graft function (DGF) on acute rejection (AR) rates and long-term graft survival. Methods We retrospectively reviewed the charts of 611 renal transplantations between 1996 and 2005. Most patients received a calcineurin inhibitor as maintenance therapy, either cyclosporine (43%) or tacrolimus (52%) and 76% of the patients received an antilymphocyte induction therapy. Study endpoints were DGF, first-year AR, and long-term graft survival. Uni- and multivariate analyses were performed to determine factors that may have influenced the study outcomes. Results DGF was observed in 16.2% of patients. Both older donor age and longer CIT were significant risk factors for DGF. DGF rates were similar whether patients received a calcineurin inhibitor before transplantation or not. AR occurred in 16.5% of grafts during the first year. Independent predictors of AR by multivariate analysis were duration of dialysis, CIT, current panel-reactive lymphocytotoxic antibody more than 5%, and the number of human leukocyte antigen-A, B, and DR mismatches. Each hour of cold ischemia increases the risk of rejection by 4%. With respect to death-censored graft survival, three pretransplant parameters emerged as independent predictors of graft loss: younger recipient age, peak panel-reactive lymphocytotoxic antibody more than 5% and longer CIT. The detrimental effect of CIT on graft survival was entirely because of its propensity to trigger AR. When AR was added to the multivariate Cox model, CIT was no longer significant whereas first-year AR became the most important predictor of graft loss (Hazards ratio, 4.6). Conclusion Shortening CIT will help to decrease not only DGF rates but also AR incidence and hence graft loss. Patients with prolonged CIT should receive adequate immunosuppression, possibly with antilymphocyte preparations, to prevent AR occurrence.

Background New immunosuppressive drugs such as anti-interleukin-2 receptor antibodies (aIL2R) and mycophenolate mofetil (MMF) have reduced the incidence of acute rejection after renal transplantation. Whether matching donor and recipient human leukocyte antigen (HLA) antigens is still relevant in patients receiving modern immunosuppression has been questioned. Methods We retrospectively analyzed the incidence and risk factors of acute rejection during the first posttransplant year and the impact of acute rejection on long-term graft survival in a cohort of 208 renal transplant patients treated with aIL2R (basiliximab, n=166; daclizumab, n=42), calcineurin inhibitors (tacrolimus, n=180; cyclosporin, n=28), mycophenolate mofetil, and steroids. Graft and patient survival were calculated by the Kaplan-Meier method. Risk factors for acute rejection were analyzed by logistic regression modeling. Results Twenty-seven patients were treated for acute rejection (26 biopsy-proven) during the first posttransplant year. The Kaplan-Meier estimate of first-year acute rejection was 13.2%. The number of HLA mismatches (odds ratio [OR] 1.65 per HLA mismatch) and long periods of dialysis before transplantation (OR 3.1 for more than 4 years of dialysis) were the only independent risk factors for first-year acute rejection. First-year acute rejection was associated with a significant reduction in overall and death-censored graft survival at 5 years after transplantation. Conclusions Although infrequent in patients receiving modern immunosuppressive drugs, acute rejection remains an important risk factor for graft loss after renal transplantation. Our results suggest that better HLA matching and shorter periods of dialysis before transplantation could reduce acute rejection rates and further improve outcomes under current immunosuppressive regimens.

Hypogammaglobulinemia (hypo-Ig) and low mannose binding protein (MBP) levels might be involved in the infectious risk in renal transplantation. In 152 kidney transplant recipients treated with calcineurin inhibitors (CNI) and mycophenolate mofetil (MMF), during the first year, we prospectively recorded the incidence of hypogammaglobulinemia, and low MBP levels. Their influence on infectious complications was evaluated in 92 patients at 3 and 12 months (T3 and T12). The proportion of deficiency increased significantly: hypo-IgG: 6% (T0), 45% (T3), and 30% (T12) (P

BACKGROUND: The incidence of new-onset posttransplant diabetes mellitus (PTDM) is increased in renal transplant patients treated with tacrolimus. METHODS: We retrospectively analyzed fasting plasma glucose and HbA1c levels as well as the dose of glucose-lowering agents in 34 renal transplant patients converted from tacrolimus to cyclosporine (CsA) for PTDM. Diabetes was defined according to current guidelines as repeated fasting plasma glucose (FPG) levels > or =126 mg/dL. RESULTS: At conversion, 11 patients received insulin, 5 received oral agents, and 18 had no glucose-lowering therapy. Fasting plasma glucose levels decreased from 146 +/- 64 mg/dL at conversion to 111 +/- 26 mg/dL at 3 months and 104 +/- 21 mg/dL at 12 months (P < .001). HbA1c levels decreased from 6.8 +/- 0.8% at conversion to 6.0 +/- 0.6% at 12 months (P = .001). Insulin was stopped in 3, the dose reduced in 7, and remained stable in 1 of the patients. The average daily insulin dose among these patients was reduced from 31 +/- 17 units at conversion to 13 +/- 12 units at 12 months (P < .05). There was no significant change in the number of patients treated with oral glucose-lowering agents. Diabetes reversed (fasting plasma glucose < or = 125 mg/dL without glucose-lowering therapy) in 44% (95% confidence interval, 23% to 64%) of patients during the first year after conversion (P < .001). Graft function, blood pressure, and lipid levels remained stable after conversion but the proportion of patients receiving lipid-lowering therapy increased from 18% to 49% (P < .01). CONCLUSIONS: Conversion from tacrolimus to CsA for PTDM was associated with a marked improvement in glucose metabolism and frequent reversal of diabetes.

Summary Tacrolimus (TRL) increases the incidence of new-onset diabetes mellitus after transplantation (NODAT). Little is known about whether conversion from TRL to cyclosporine A (CsA) improves glucose metabolism in patients with NODAT. We retrospectively analysed glucose metabolism parameters in 54 TRL-treated renal transplant patients who developed NODAT. Thirty-four were converted to CsA whereas 20 patients continued TRL. After conversion, fasting plasma glucose decreased from 146 ± 64 to 104 ± 20 mg/dl (P < 0.0001) and HbA1c levels decreased from 6.8 ± 0.8% to 6.0 ± 0.6% (P < 0.0001) after 1 year of follow-up. The remission rate of NODAT reached 42% (95% confidence interval 24‐59%) 1 year after conversion versus 0% in the control group (P = 0.001). Blood pressure and lipid levels were stable after conversion although the use of statins significantly increased (P < 0.01). The conversion was safe in terms of graft function and acute rejection episodes. The 1-year patient survival and graft survival rate were 100%. In conclusion, our results suggest a significant improvement of glucose metabolism after conversion to CsA in renal transplant patients with NODAT.

Genetic factors are suspected in the pathogenesis of IgA nephropathy, as well as in the course of IgA nephropathy progression towards end stage renal failure. UMOD polymorphism rs12917707 is known to associate with end stage renal failure of mixed aetiologies., SCOPUS: ar.j, info:eu-repo/semantics/published