First Year Renal Function as a Predictor of Kidney Allograft Outcome

The Impact of Hematological Indices on the Occurrence of Delayed Graft Function (DGF) of Transplanted Kidney

BACKGROUND

to analyse the effect of haematological indices on the occurrence of Delayed Graft Function (DGF) in patients undergoing kidney transplantation and on the function of the transplanted kidney on the 7th postoperative day.

METHODS

365 recipients who underwent kidney transplantation from a donor with known brain death between 2010 and 2017 were included in this retrospective study. Information from patient medical records, donor medical records, and donation and transplantation protocols was used for analysis. Statistica 13 was used for statistical analysis.

RESULTS

In the study group, DGF occurred in 144 recipients (39.45%), and Non-Graft Function (NGF) occurred in 12 recipients (3.29%). Recipients who developed DGF had a significantly higher Neutrophil/Monocyte Ratio (NMR) before renal transplantation (p = 0.048), a lower NMR value on postoperative day 1 (p < 0.001), and a difference between the values on day 1 and before surgery (p < 0.001). In addition, they had a significantly lower Lymphocyte/Monocyte Ratio (LMR) on postoperative day 1 LMR 1 (p < 0.001). It was shown that the value of the indices based on the ROC curve-NMR1 > 29.29, NMR1-0 > 22.71, and LMR1 > 1.74 (respectively: AUC = 0.624; 95% CI 0.566-0.682; and p < 0.001/AUC = 0.622; 95% CI 0.563-0.680; and p < 0.001/AUC = 0.610; 95% CI 0.550-0.670; and p < 0.001)-can be used to identify recipients with a significant probability of DGF.

CONCLUSIONS

the NMR and LMR parameters on the first postoperative day and the difference between the NMR values on the first post-transplant day and the first pre-transplant day are predictive factors associated with the risk of DGF.

Estimated Renal Metabolomics at Reperfusion Predicts One-Year Kidney Graft Function

Renal transplantation is the gold-standard procedure for end-stage renal disease patients, improving quality of life and life expectancy. Despite continuous advancement in the management of post-transplant complications, progress is still needed to increase the graft lifespan. Early identification of patients at risk of rapid graft failure is critical to optimize their management and slow the progression of the disease. In 42 kidney grafts undergoing protocol biopsies at reperfusion, we estimated the renal metabolome from RNAseq data. The estimated metabolites' abundance was further used to predict the renal function within the first year of transplantation through a random forest machine learning algorithm. Using repeated K-fold cross-validation we first built and then tuned our model on a training dataset. The optimal model accurately predicted the one-year eGFR, with an out-of-bag root mean square root error (RMSE) that was 11.8 ± 7.2 mL/min/1.73 m2. The performance was similar in the test dataset, with a RMSE of 12.2 ± 3.2 mL/min/1.73 m2. This model outperformed classic statistical models. Reperfusion renal metabolome may be used to predict renal function one year after allograft kidney recipients.

A comparison of post-transplant renal function in pre-emptive and post-dialysis pediatric kidney transplant recipients

PURPOSE

Little is known regarding post-transplant renal function following pediatric pre-emptive KT. Therefore, this study aims to determine whether there is a difference in 1 year post-transplant renal function outcomes between pre-emptive and post-dialysis KT in pediatric transplant recipients.

METHODS

A retrospective review of patients who underwent kidney transplant at our institution between 2000 and 2015 was performed. Kidney transplant recipients were divided into four groups: pre-DD, post-DD, pre-LD, and post-LD. The clinical outcomes, measured in eGFR (mL/min/1.73 m² ), acute rejection episodes within 1 year, and hospitalization within 1 year were compared to between groups in their respective donor types (pre-DD vs post-DD; pre-LD vs post-LD).

RESULTS

The 324 patients were identified (21 pre-DD, 151 post-DD, 54 pre-LD, and 98 post-LD). Post-DD group had more females (P = 0.018) and post-operative complications (P = 0.023), although there was no difference in complications requiring intervention (P = 0.129). Post-LD patients were more likely to be females (P = 0.017) and those with intrinsic renal (non-urological/structural) ESRD etiology (P = 0.003). The 1-year eGFR was similar between pre-DD and post-DD groups (70.3 [IQR 53.5-88.5] vs 74.3 [IQR 62.3-90.5], P = 0.613), as well as pre-LD and post-LD groups (66.6 [IQR 47.8-73.7] vs 63.9 [IQR 55.0-77.1], P = 0.600). There were no significant differences in rates of acute rejection episodes or hospitalization within 1 year of transplantation for in LD/DD groups.

CONCLUSION

There is no significant difference in renal function at 1 year post-transplant in pediatric patients receiving pre-emptive or post-dialysis kidney transplants.

Pre-transplant histology does not improve prediction of 5-year kidney allograft outcomes above and beyond clinical parameters

Pre-implant kidney biopsy is used to determine suitability of marginal donor kidneys for transplantation. However, there is limited data examining the utility of pre-implant histology in predicting medium term graft outcome. This retrospective study examined kidney transplants over a 10-year period at a single center to determine if pre-implant histology can identify cases of eGFR ≤35 ml/min/1.73m² at 5 year follow up beyond a clinical predictive logistic regression model. We also compared outcomes of dual kidney transplants with standard single kidney transplants. Of 1195 transplants, 171 received a pre-implant kidney biopsy and 15 were dual transplants. There was no significant difference in graft and patient survival rates. Median eGFR was lower in recipients of biopsied kidneys compared with standard kidney transplants (44 vs. 54 ml/min/1.73m², p < .001). Median eGFR of dual transplant and standard kidney transplants were similar (58 vs. 54 ml/min/1.73m², p = .64). Glomerular sclerosis (p = .05) and Karpinski Score (p = .03) were significant predictors of eGFR at 5-years in multivariate analysis but did not improve discrimination of eGFR ≤35 ml/min/1.73m² at 5-years beyond a clinical prediction model comprising donor age, donor hypertension and terminal donor creatinine (C-statistic 0.67 vs. 0.66; p = .647). Pre-implant histology did not improve prediction of medium-term graft outcomes beyond clinical predictors alone. Allograft function of dual transplant kidneys was similar to standard transplants, suggesting that there is scope to increase utilization of kidneys considered marginal based on histology.

Decreasing Estimated Glomerular Filtration Rate Is Associated With Increased Risk of Hospitalization After Kidney Transplantation

INTRODUCTION

Following renal transplantation, decreased renal function is associated with increased risk of cardiovascular disease, graft loss and mortality. We investigated whether declining renal function was associated with hospitalization post-transplant.

METHODS

Adult, first-time, kidney transplant recipients between 2004 and 2006 from the United Network for Organ Sharing database and hospitalizations one year after the 6-month post-transplant follow-up visit were examined. Generalized linear models explored the relationship between estimated glomerular filtration rate (eGFR) measured at 6 months and the number of hospitalizations in the following year.

RESULTS

Of 15,778 kidney transplant recipients, 19.1% were admitted in the year after the 6-month follow-up visit. Among those hospitalized, the mean number of hospitalizations was 1.71 and increased with decreasing eGFR. In multivariable models, a decrease in eGFR was significantly associated with increased hospitalizations: for every 10 ml/min/1.73m² decrease in eGFR, there was an 11% increase in hospitalization rate (p <0.001). Lower eGFR after the first 6 months following transplantation was associated with an increase in late hospitalizations among adult kidney transplant recipients.

DISCUSSION

Identifying patients with declining eGFR and other risk factors may help prevent morbidity and mortality associated with hospitalization post-transplantation.

Derivation of a Predictive Model for Graft Loss Following Acute Kidney Injury in Kidney Transplant Recipients

Background:

Acute kidney injury (AKI) is common in the kidney transplant population.

Objective:

To derive a multivariable survival model that predicts time to graft loss following AKI.

Design:

Retrospective cohort study using health care administrative and laboratory databases.

Setting:

Southwestern Ontario (1999-2013) and Ottawa, Ontario, Canada (1996-2013).

Patients:

We included first-time kidney only transplant recipients who had a hospitalization with AKI 6 months or greater following transplant.

Measurements:

AKI was defined using the Acute Kidney Injury Network criteria (stage 1 or greater). The first episode of AKI was included in the analysis. Graft loss was defined by return to dialysis or repeat kidney transplant.

Methods:

We performed a competing risk survival regression analysis using the Fine and Gray method and modified the model into a simple point system. Graft loss with death as a competing event was the primary outcome of interest.

Results:

A total of 315 kidney transplant recipients who had a hospitalization with AKI 6 months or greater following transplant were included. The median (interquartile range) follow-up time was 6.7 (3.3-10.3) years. Graft loss occurred in 27.6% of the cohort. The final model included 6 variables associated with an increased risk of graft loss: younger age, increased severity of AKI, failure to recover from AKI, lower baseline estimated glomerular filtration rate, increased time from kidney transplant to AKI admission, and receipt of a kidney from a deceased donor. The risk score had a concordance probability of 0.75 (95% confidence interval [CI], 0.69-0.82). The predicted 5-year risk of graft loss fell within the 95% CI of the observed risk more than 95% of the time.

Limitations:

The CIs of the estimates were wide, and model overfitting is possible due to the limited sample size; the risk score requires validation to determine its clinical utility.

Conclusions:

Our prognostic risk score uses commonly available information to predict the risk of graft loss in kidney transplant patients hospitalized with AKI. If validated, this predictive model will allow clinicians to identify high-risk patients who may benefit from closer follow-up or targeted enrollment in future intervention trials designed to improve outcomes.

Understanding Trends in Kidney Function 1 Year after Kidney Transplant in the United States

Lower eGFR 1 year after kidney transplant is associated with shorter allograft and patient survival. We examined how practice changes in the past decade correlated with time trends in average eGFR at 1 year after kidney transplant in the United States in a cohort of 189,944 patients who received a kidney transplant between 2001 and 2013. We calculated the average eGFR at 1 year after transplant for the recipient cohort of each year using the appropriate Modification of Diet in Renal Disease equation depending on the prevailing methodology of creatinine measurement, and used linear regression to model the effects of practice changes on the national post-transplant eGFR trend. Between the 2001-2005 period and the 2011-2013 period, average 1-year post-transplant eGFR remained essentially unchanged, with differences of 1.34 (95% confidence interval, 1.03 to 1.65) ml/min per 1.73 m² and 0.66 (95% confidence interval, 0.32 to 1.01) ml/min per 1.73 m² among deceased and living donor kidney transplant recipients, respectively. Over time, the mean age of recipients increased and more marginal organs were used; adjusting for these trends unmasked a larger temporal improvement in post-transplant eGFR. However, changes in immunosuppression practice had a positive effect on average post-transplant eGFR and balanced out the negative effect of recipient/donor characteristics. In conclusion, average 1-year post-transplant eGFR remained stable, despite increasingly unfavorable attributes in recipients and donors. With an aging ESRD population and continued organ shortage, preservation of average post-transplant eGFR will require sustained improvement in immunosuppression and other aspects of post-transplant care.

Depression, Anxiety, Resilience and Coping Pre and Post Kidney Transplantation - Initial Findings from the Psychiatric Impairments in Kidney Transplantation (PI-KT)-Study

PURPOSE

Depression/anxiety, impaired Health-Related Quality of Life (HRQoL) and coping and resilience structures, are associated with increased mortality/poor outcome in chronic kidney disease (CKD) patients before (CKD/pre-KT) and after kidney (CKD-T) transplantation. Less is known about prevalence rates of psychiatric symptoms and impaired HRQoL of non-transplanted compared with transplanted patients.

METHODS

In a cross-sectional study comparing 101 CKD/pre-KT patients with 151 cadaveric-transplanted (CKD-T) patients, we examined prevalence of depression/anxiety (HADS questionnaire) and coping, resilience and HRQoL (SF-12, Resilience-Scale and FKV-questionnaire).

RESULTS

The prevalence of both depressive and anxiety symptoms was not significantly different between different pre-/and CKD-T patient groups. In CKD-T no significant relations of coping strategies with kidney function were identified. Furthermore, the Resilience Scales for acceptance and competence did not suggest any differences between the CKD/pre-KT and CKD-T subgroup. In the CKD/pre-KT patients, significant correlations were identified between the acceptance subscale and partnership, as well as between the competence subscale and older age/partnership.

CONCLUSIONS

Both the CKD/pre-KT and CKD-T patients exhibited notable impairments in the HRQoL which which showed a comparable pattern of results. KT itself does not appear to be the main risk factor for the development of mental impairments.

Factors affecting eGFR 5-year post-deceased donor renal transplant: analysis and predictive model

AIM

Long-term survival of renal allografts has improved over the last 20 years. However, less is known about current expectations for long-term allograft function as determined by estimated glomerular filtration rate (eGFR). The aim of this study was to investigate factors which affect graft function at 5 years' post-renal transplantation. The statistically significant factors were then used to construct a predictive model for expected eGFR at five years' post-transplant.

METHODS

We retrospectively reviewed all adult patients who received a renal transplant in the Republic of Ireland between 1990 and 2004. Data collected included era of transplantation (1990-1994, 1995-1999, 2000-2004), donor and recipient age and gender, number of human leucocyte antigen mismatches, cold ischemia time (CIT), number of prior renal transplants, immunosuppressive regimen used and acute rejection episodes. Estimated GFR was calculated at 5 years after transplantation from patient data using the Modified Diet in Renal Disease (MDRD) equation. Consecutive sampling was used to divide the study population into two equal unbiased groups of 489 patients. The first group (derivation cohort) was used to construct a predictive model for eGFR five years' post-transplantation, the second (validation cohort) to test this model.

RESULTS

Nine hundred and seventy eight patients were analyzed. The median age at transplantation was 43 years (range 18-78) and 620 (63.4%) were male. One hundred and seventy five patients (17.9%) had received a prior renal transplant. Improved eGFR at five years' post-transplantation was associated with tacrolimus-based combination immunosuppression, younger donor age, male recipient, absence of cytomegalovirus disease and absence of acute rejection episodes as independently significant factors (p < 0.05). The predictive model developed using these factors showed good correlation between predicted and actual median eGFR at five years. The model explained 20% of eGFR variability. The validation model findings were consistent with the derivation model (21% variability of eGFR explained by model using same covariates on new data).

CONCLUSION

The predictive model we have developed shows good correlation between predicted and actual median eGFR at five years' post-transplant. Applications of this model include comparison of current and future therapy options such as new immunosuppressive regimens.

Urinary calprotectin and posttransplant renal allograft injury

Objective

Current methods do not predict the acute renal allograft injury immediately after kidney transplantation. We evaluated the diagnostic performance of urinary calprotectin for predicting immediate posttransplant allograft injury.

Methods

In a multicenter, prospective-cohort study of 144 incipient renal transplant recipients, we postoperatively measured urinary calprotectin using an enzyme-linked immunosorbent assay and estimated glomerular filtration rate (eGFR) after 4 weeks, 6 months, and 12 months.

Results

We observed a significant inverse association of urinary calprotectin concentrations and eGFR 4 weeks after transplantation (Spearman r = −0.33; P<0.001). Compared to the lowest quartile, patients in the highest quartile of urinary calprotectin had an increased risk for an eGFR less than 30 mL/min/1.73 m² four weeks after transplantation (relative risk, 4.3; P<0.001; sensitivity, 0.92; 95% CI, 0.77 to 0.98; specificity, 0.48; 95% CI, 0.31 to 0.66). Higher urinary calprotectin concentrations predicted impaired kidney function 4 weeks after transplantation, as well as 6 months and 12 months after transplantation. When data were analyzed using the urinary calprotectin/creatinine-ratio similar results were obtained. Urinary calprotectin was superior to current use of absolute change of plasma creatinine to predict allograft function 12 months after transplantation. Urinary calprotectin predicted an increased risk both in transplants from living and deceased donors. Multivariate linear regression showed that higher urinary calprotectin concentrations and older donor age predicted lower eGFR four weeks, 6 months, and 12 months after transplantation.

Conclusions

Urinary calprotectin is an early, noninvasive predictor of immediate renal allograft injury after kidney transplantation.

Health-related quality of life 3 months after kidney transplantation as a predictor of survival over 10 years: a longitudinal study

AIM

This study explores the association between kidney function, side effects of immunosuppressive treatment, coping self-efficacy, and physical and mental HRQoL at 3 months (baseline) after kidney transplantation (KT) and their impact on patient and graft survival for up to 10 years (follow-up).

METHODS

A group of 151 patients provided at baseline their socioeconomic and medical (CKD-EPI) data and completed the End-Stage Renal Disease Symptom Checklist (perceived side effects), the coping self-efficacy scale, and the SF-36. At follow-up, patients' health status was noted. Univariate GLM exploring the main effects of the independent variables on physical and mental HRQoL was performed; furthermore, Cox regression analyses were performed to determine whether the early posttransplantation factors predicted patient and graft survival.

RESULTS

Less severe side effects of immunosuppressive treatment and higher efficacy in stopping unpleasant emotions were associated with both higher physical and mental HRQoL at baseline. Younger age was associated with higher physical HRQoL and older age, and lower efficacy in getting support from family and friend were associated with higher mental HRQoL. Patients reporting higher physical and mental HRQoL at 3 months and with higher age and better kidney function had higher odds of surviving with a functioning graft.

CONCLUSION

Older age, higher kidney function, and higher physical and mental HRQoL at baseline significantly improved the odds of graft and patient survival over 10 years. These results show the importance of close monitoring of early posttransplantation HRQoL along with kidney function and reported side effects because of their effect on long-term patient outcomes.

Do we need a different organ allocation system for kidney transplants using donors after circulatory death?

BACKGROUND

There is no national policy for allocation of kidneys from Donation after circulatory death (DCD) donors in the UK. Allocation is geographical and based on individual/regional centre policies. We have evaluated the short term outcomes of paired kidneys from DCD donors subject to this allocation policy.

METHODS

Retrospective analysis of paired renal transplants from DCD's from 2002 to 2010 in London. Cold ischemia time (CIT), recipient risk factors, delayed graft function (DGF), 3 and 12 month creatinine) were compared.

RESULTS

Complete data was available on 129 paired kidneys.115 pairs were transplanted in the same centre and 14 pairs transplanted in different centres. There was a significant increase in CIT in kidneys transplanted second when both kidneys were accepted by the same centre (15.5 ± 4.1 vs 20.5 ± 5.8 hrs p<0.0001 and at different centres (15.8 ± 5.3 vs. 25.2 ± 5.5 hrs p=0.0008). DGF rates were increased in the second implant following sequential transplantation (p=0.05).

CONCLUSIONS

Paired study sequential transplantation of kidneys from DCD donors results in a significant increase in CIT for the second kidney, with an increased risk of DGF. Sequential transplantation from a DCD donor should be avoided either by the availability of resources to undertake simultaneous procedures or the allocation of kidneys to 2 separate centres.

The impact of ICAM1 and VCAM1 gene polymorphisms on chronic allograft nephropathy and transplanted kidney function

ICAM-1 and VCAM-1 adhesion molecules play important roles in the immune response and emergence of chronic allograft nephropathy (CAN). The several polymorphisms of ICAM1 and VCAM1 genes are associated with changes in molecular expression therefore affecting allograft function and immune responses after kidney transplantation. The aim of this study was to examine the impact of polymorphisms in ICAM1 and VCAM1 genes on biopsy-proven CAN and renal allograft function. The 270 Caucasian renal transplant recipients (166 men and 104 women) were genotyped for the rs5498 ICAM1 and rs1041163 and rs3170794 VCAM1 gene polymorphisms using real-time polymerase chain reaction. There was no correlation between polymorphisms and CAN. Creatinine concentrations in the first month after transplantation differed between the rs5498 ICAM1 genotypes (P = .095), being higher for GG carriers (AA + AG vs GG, P =.07) albeit not with statistical significance. Creatinine concentrations at 12, 24, and 36 months after transplantation differed significantly among rs5498 ICAM1 genotypes (P = .0046, P =.016, and P = .02) and were higher among GG carriers (AA + AG vs GG, P = .001, P = .004, and P = .006). Rs5498 ICAM1 GG genotype and receipient male gender were independent factors associated with higher creatinine concentrations. These results suggest that the rs5498 ICAM1 GG genotype may be associated with long-term allograft function.

Influence of renal function on long-term graft survival and patient survival in renal transplant recipients

OBJECTIVES

Renal function post kidney transplantation is an outcome of interest for both clinicians and regulators evaluating immunosuppressive treatments post-transplantation. The current review sought to provide a synopsis of currently available literature examining the relationship between post-transplantation renal function and long-term graft survival and patient survival.

METHODS

A systematic literature review was performed using the PubMed, EMBASE and Cochrane Library databases. The search strategy was designed based on high level Medical Subject Heading (MeSH) terms and designed to capture studies published in English to 2012 and identified a total of 2683 unique hits; for inclusion studies were required to have >100 patients. Following two rounds of screening, a total of 27 studies were included in the final review (26 of which were identified via the literature review and one study was identified via searches of the reference sections of included studies).

RESULTS

The consensus among studies was that lower post-transplantation GFR, in particular 12 month GFR, was consistently and significantly associated with an increased risk for overall graft loss, death-censored graft loss and all-cause mortality in both univariate and multivariate analyses. The magnitude of the association between reduced GFR and outcomes was greater for death-censored graft loss versus overall graft loss and for graft loss in comparison with overall patient mortality. The predictive utility of GFR alone in predicting long-term outcomes was reported to be limited.

CONCLUSIONS

Lower GFR and greater rates of decline in GFR post-transplantation are associated with an increased risk for graft loss (overall and death-censored) and all-cause mortality; however, the predictive utility of GFR alone in predicting long-term outcomes is limited.

Early expression profile of inflammatory markers and kidney allograft status

Cellular rejection after renal transplantation, in general, occurs as a result of an interaction between immunologic processes that maintain graft tolerance versus allograft rejection. A potential mechanism that triggers such processes might be through the activation of the innate immune response initiated during organ procurement and ischemia/reperfusion injury, contributing to delayed graft function or graft dysfunction. Our goal was to test the impact of molecular markers that have key roles in innate immunity such as cytokines, Toll-like receptors (TLRs), and allograft inflammatory factor-1 (AIF- 1) at early times after transplantation. Blood samples from a total of 90 patients who received kidney transplants were included in this study. Three samples from each patient at different time intervals (pretransplantation, day 3, and day 6 after transplantation) were tested using a quantitative reverse transcriptase polymerase chain reaction. The mRNA transcripts were tested in association with glomerular filtration rates (GFR) as a measure of allograft function. Surgical samples obtained from transplant nephrectomy were used in a tissue array for immunohistochemistry testing. In peripheral blood mononuclear cells, the mean ± standard error of mean (SEM) for interleukin 18 (IL-18), and IL-10 mRNA expression were increased and interferon-γ was decreased in association with high GFR post-transplantation as compared with the pretransplantation expression levels. The mean ± SEM for expression level of AIF-1 was increased 1.5-fold and for TLR-2 and TLR-4 were increased 1.2 to 1.4-fold in samples obtained on day 6 post-transplantation in association with low GFR (P < .05). In neutrophils, the mean ± SEM levels of TLR-2 mRNA was increased 2-fold on day 6 in association with high GFR (P < .005), but was reduced 2.8-fold in association with low GFR (P < .002). In conclusion, the mRNA profiles of biomarkers presented here appeared to be informative for prediction of allograft status and outcome.

The rate of decline of glomerular filtration rate is a predictor of long-term graft outcome after kidney transplantation

BACKGROUND

To improve the long-term outcome of kidney transplantation (KT), it is important to identify and take active steps to reduce the number or severity of novel risk factors. We investigated whether changes in estimated glomerular filtration rate over the first year after KT (ΔeGFR12-3) was associated with long-term renal allograft function and survival.

METHODS

Four hundred twenty-eight allograft recipients transplanted between 1990 and 2001 underwent ΔeGFR12-3 calculation using the equation: ΔeGFR12-3 = ([eGFR at 12 months post-KT - eGFR at 3 months post-KT]/[eGFR at 3 months post-KT]) × 100%. Recipients were divided into 3 groups according to their ΔeGFR12-3: group I (n = 150), ΔeGFR12-3 ≥ 10%; group II (n = 151), 10 > ΔeGFR12-3 ≥ -10%; and group III (n = 127), ΔeGFR12-3 < -10%. Multiple linear regression analysis was used to adjust for confounding variables that may affect long-term renal allograft function, and Kaplan-Meier analysis, to compare allograft survival.

RESULTS

At a mean follow-up of 120 ± 58 months, we observed 112 renal allograft losses. The ΔeGFR over 10 years post-KT (ΔeGFR120-3) was significantly associated with the serum uric acid levels at 3 months post-transplantation and ΔeGFR12-3. Group III showed poor renal allograft survival; group I, 194 ± 8 months; group II, 197 ± 7 month and; group III, 163 ± 4 months; (log-rank test, P < .05). A Cox proportional hazard model revealed ΔeGFR12-3 to be independently associated with future renal allograft loss (hazard ratio, 0.981; 95% confidence interval, 0.974-0.992).

CONCLUSION

Our results suggested that ΔeGFR12-3 may be an independent predictor of kidney allograft survival. Routine application of eGFR is strongly recommended to identify patients at risk for chronic allograft dysfunction.

Randomized trial of everolimus-facilitated calcineurin inhibitor minimization over 24 months in renal transplantation

BACKGROUND

Strategies allowing calcineurin inhibitor minimization while maintaining efficacy may improve renal transplant outcomes.

METHODS

A2309 was a 24-month, phase IIIb, open-label trial of 833 de novo renal transplant recipients randomized to everolimus, targeting trough concentrations of 3-8 or 6-12 ng/mL plus reduced-exposure cyclosporine A (CsA) or to mycophenolic acid (MPA) 1.44 g per day plus standard-exposure CsA. All patients received basiliximab ± corticosteroids. The incidence of the primary composite efficacy endpoint and its components (treated biopsy-proven acute rejection, graft loss, death, or loss to follow-up), renal function (serum creatinine and estimated glomerular filtration rate), and adverse events (AEs) were compared at 24 months; as per the protocol, these analyses were not noninferiority.

RESULTS

Composite efficacy failure rates (95% confidence interval for difference vs. MPA) were 32.9% (-2.2%, 13.0%), 26.9% (-7.9%, 6.8%), and 27.4% at month 24 in the everolimus 3-8 and 6-12 ng/mL and MPA groups, respectively. Mean estimated glomerular filtration rate (Modification of Diet in Renal Disease) at month 24 was 52.2 (-2.1, 5.5 mL/min/1.73 m(2)), 49.4 (-4.8, 2.7 mL/min/1.73 m(2)), and 50.5 mL/min/1.73 m(2), respectively. AEs were generally mild to moderate in severity and comparable between the groups. AEs leading to discontinuation were reported in 28.5% (P = 0.03 vs. MPA), 30.6% (P = 0.007 vs. MPA), and 20.5% of patients receiving everolimus 3-8 and 6-12 ng/mL and MPA, respectively.

CONCLUSIONS

Everolimus trough concentrations targeted to 3-8 ng/mL, along with a greater than 60% reduction in CsA exposure, was associated with comparable efficacy and renal function versus MPA plus standard-exposure CsA over the 2-year period. A significantly higher incidence of AEs led to discontinuation in the everolimus groups compared with the MPA group.

Belatacept utilization recommendations: an expert position

INTRODUCTION

There is a continuing need for an immunosuppressive therapy that offers a high benefit-risk profile for renal transplant recipients, supporting long-term patient and graft survival while minimizing cumulative nephrotoxicity and other side effects. Belatacept , the first biological agent developed for primary maintenance immunosuppression, was recently approved for use in Europe. Belatacept combined with corticosteroids and a mycophenolic acid is indicated for prophylaxis of graft rejection in adults receiving renal transplant. Its use is contraindicated in Epstein-Barr virus seronegative or serostatus unknown patients due to increased risk of developing posttransplant lymphoproliferative disorder.

AREAS COVERED

This review provides practical recommendations for the use of belatacept, based on safety and efficacy data from Phase II and Phase III clinical trials in de novo kidney transplant recipients.

EXPERT OPINION

Treatment with belatacept is associated with improved long-term graft function, making belatacept an important option for prevention of kidney allograft rejection. Furthermore, efficacy and safety data over several years of therapy suggest that belatacept is particularly suitable for long-term immunosuppression, and the selective targeting offered by belatacept may help avoid some of the non-specific chronic safety risks associated with calcineurin inhibitors and steroids. Future studies will clarify the optimal regimen for belatacept usage.

Induction therapy by anti-thymocyte globulin (rabbit) versus basiliximab in deceased donor renal transplants and the effect on delayed graft function and outcomes

The use of induction therapy significantly reduces the incidence of acute rejection (AR) episodes posttransplantation and prevents delayed graft function (DGF). In our program, all adult deceased donor kidney transplant (DDKT) recipients receive immunosuppression induction therapy with either basiliximab (anti-CD25 Ab) or rabbit anti-thymocyte globulin (RATG). Our protocol is risk adjusted such that patients who are at a higher risk for DGF or AR received RATG and all other patients receive anti-CD25 Ab. We hypothesized that treating our higher-risk patients with RATG induction at the time of transplantation would lead to a lower rate of DGF and better outcomes. From August 1, 2005 through August 31, 2010, 116 consecutive adult patients received a DDKT in a single academic transplantation center. All DDKT patients received induction with RATG or anti-CD25 Ab. The induction decision was made prior to transplantation based on donor and recipient risk factors for AR and DGF. Transplants that were deemed at higher risk for DGF or AR based on donor factors or recipient factors received RATG. Medical records and patient databases were reviewed retrospectively. The use of RATG in higher-risk recipients for DGF and AR did not significantly reduce the DGF rate. At 6 months the function of the allograft function measured as creatinine clearance or serum creatinine was lower in the RATG group than the patients who received anti-CD25 Ab induction. The choice of induction therapy did not improve outcomes in high-risk patients in this short-term study.

Incremental peritoneal dialysis favourably compares with hemodialysis as a bridge to renal transplantation

Background. The value of incremental peritoneal dialysis (PD) as a bridge to renal transplantation (Tx) has not been specifically addressed. Methods. All consecutive Stage 5 CKD patients with at least 1 year predialysis followup, starting incremental PD or HD under our care and subsequently receiving their first renal Tx were included in this observational cohort study. Age, gender, BMI, underlying nephropathy, residual renal function (RRF) loss rate before dialysis and RRF at RRT start, comorbidity, RRT schedules and adequacy measures, dialysis-related morbidity, Tx waiting time, RRF at Tx, incidence of delayed graft function (DGF), in-hospital stay for Tx, serum creatinine at discharge and one year later were collected and compared between patients on incremental PD or HD before Tx. Results. Seventeen patients on incremental PD and 24 on HD received their first renal Tx during the study period. Age, underlying nephropathy, RRF loss rate in predialysis, RRF at the start of RRT and comorbidity did not differ significantly. While on dialysis, patients on PD had significantly lower epoetin requirements, serum phosphate, calciumxphosphate product and better RRF preservation. Delayed graft function (DGF) occurred in 12 patients (29%), 1 on incremental PD and 11 on HD. Serum creatinine at discharge and 1 year later was significantly higher in patients who had been on HD. Conclusions. In patients receiving their first renal Tx, previous incremental PD was associated with low morbidity, excellent preservation of RRF, easier attainment of adequacy targets and significantly better immediate and 1-year graft function than those observed in otherwise well-matched patients previously treated with HD.

The association of -262C/T polymorphism in the catalase gene and delayed graft function of kidney allografts

BACKGROUND

Catalase is an intracellular antioxidant enzyme that is mainly located in cellular peroxisomes and in the cytosol. This enzyme plays a significant role in the development of tolerance to oxidative stress in the adaptive response of cells and tissues. The aim of the present study was to examine the association between the -262C/T polymorphism in the catalase gene and delayed graft function (DGF), acute rejection and chronic allograft nephropathy of kidney allografts.

METHODS

One hundred eighty-seven recipients of first renal transplants were included in the study. The histories of the patients were analysed regarding DGF, acute rejection and chronic allograft nephropathy. The polymorphism -262C/T in the catalase gene was analysed using the polymerase chain reaction--restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

The risk of DGF was significantly lower in T allele carriers compared with CC homozygotes: odds ratio = 0.34, 95% confidence interval = 0.17-0.67, P = 0.001. There were no statistically significant associations between the studied polymorphism and acute rejection or chronic allograft nephropathy.

CONCLUSION

The results of this study suggest that -262C/T polymorphism in the catalase gene is associated with DGF in kidney allograft recipients.

Everolimus plus reduced-exposure CsA versus mycophenolic acid plus standard-exposure CsA in renal-transplant recipients

Everolimus allows calcineurin-inhibitor reduction without loss of efficacy and may improve renal-transplant outcomes. In a 24-month, open-label study, 833 de novo renal-transplant recipients were randomized to everolimus 1.5 or 3.0 mg/day (target troughs 3-8 and 6-12 ng/mL, respectively) with reduced-exposure CsA, or mycophenolic acid (MPA) 1.44 g/day plus standard-exposure CsA. Patients received basiliximab +/- corticosteroids. The primary endpoint was composite efficacy failure (treated biopsy-proven acute rejection, graft loss, death or loss to follow-up) and the main safety endpoint was renal function (estimated glomerular filtration rate [eGFR], by Modification of Diet in Renal Disease [MDRD]) at Month 12 (last-observation-carried-forward analyses). Month 12 efficacy failure rates were noninferior in the everolimus 1.5 mg (25.3%) and 3.0 mg (21.9%) versus MPA (24.2%) groups. Mean eGFR at Month 12 was noninferior in the everolimus groups versus the MPA group (54.6 and 51.3 vs 52.2 mL/min/1.73 m(2) in the everolimus 1.5 mg, 3.0 mg and MPA groups, respectively; 95% confidence intervals for everolimus 1.5 mg and 3.0 mg vs MPA: -1.7, 6.4 and -5.0, 3.2, respectively). The overall incidence of adverse events was comparable between groups. The use of everolimus with progressive reduction in CsA exposure, up to 60% at 1 year, resulted in similar efficacy and renal function compared with standard-exposure CsA plus MPA.