Interaction between acute rejection and recipient age on long-term renal allograft survival

Characterizing the risk of human leukocyte antigen-incompatible living donor kidney transplantation in older recipients

Older compatible living donor kidney transplant (CLDKT) recipients have higher mortality and death-censored graft failure (DCGF) compared to younger recipients. These risks may be amplified in older incompatible living donor kidney transplant (ILDKT) recipients who undergo desensitization and intense immunosuppression. In a 25-center cohort of ILDKT recipients transplanted between September 24, 1997, and December 15, 2016, we compared mortality, DCGF, delayed graft function (DGF), acute rejection (AR), and length of stay (LOS) between 234 older (age ≥60 years) and 1172 younger (age 18-59 years) recipients. To investigate whether the impact of age was different for ILDKT recipients compared to 17 542 CLDKT recipients, we used an interaction term to determine whether the relationship between posttransplant outcomes and transplant type (ILDKT vs CLDKT) was modified by age. Overall, older recipients had higher mortality (hazard ratio: 1.632.072.65, P < .001), lower DCGF (hazard ratio: 0.360.530.77, P = .001), and AR (odds ratio: 0.390.540.74, P < .001), and similar DGF (odds ratio: 0.461.032.33, P = .9) and LOS (incidence rate ratio: 0.880.981.10, P = 0.8) compared to younger recipients. The impact of age on mortality (interaction P = .052), DCGF (interaction P = .7), AR interaction P = .2), DGF (interaction P = .9), and LOS (interaction P = .5) were similar in ILDKT and CLDKT recipients. Age alone should not preclude eligibility for ILDKT.

Maximizing opportunities for kidney transplantation in older adults

PURPOSE OF REVIEW

To summarize the current state of evidence related to the outcomes of older adults who need and receive kidney transplants, and strategies to facilitate appropriate transplant access in this at-risk group.

RECENT FINDINGS

Older adults are a rapidly growing subgroup of the kidney transplant waitlist. Compared to younger adults, older kidney transplant recipients have increased mortality after kidney transplant and lower death-censored graft survival. In determining suitability for transplantation in older patients, clinicians must balance procedural and immunosuppression-related risk with incremental survival when compared with dialysis. To appropriately increase access to transplantation in this population, clinicians and policy makers consider candidates' chronological age and frailty, as well as the quality of and waiting time for a donated allograft. Given risk of deterioration prior to transplant, candidates should be rapidly evaluated, listed, and transplanted using living donor and or less than ideal deceased donor organs when available.

SUMMARY

Access to transplantation for older adults can be increased through targeted interventions to address frailty and reduce waiting times through optimized organ use. Focused study and educational interventions for patients and providers are needed to improve the outcomes of this vulnerable group.

The aging of the immune system and its implications for transplantation

By the last third of life, most mammals, including humans, exhibit a decline in immune cell numbers, immune organ structure, and immune defense of the organism, commonly known as immunosenescence. This decline leads to clinical manifestations of increased susceptibility to infections, particularly those caused by emerging and reemerging microorganisms, which can reach staggering levels-infection with SARS-CoV-2 has been 270-fold more lethal to older adults over 80 years of age, compared to their 18-39-year-old counterparts. However, while this would be expected to be beneficial to situations where hyporeactivity of the immune system may be desirable, this is not always the case. Here, we discuss the cellular and molecular underpinnings of immunosenescence as they pertain to outcomes of solid organ and hematopoietic transplantation.

Kidney Transplant Outcomes in elderly Recipients: An Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry Study

BACKGROUND

There is an increase in elderly patients receiving kidney transplant internationally. This study describes elderly kidney transplant recipient outcomes in Australia and New Zealand.

METHODS

The study included all adult first kidney transplant recipients in Australia and New Zealand from 2000 to 2015. Survival and graft outcomes were compared between elderly (≥70 years) and younger (18-69 years) recipients using Cox proportional hazards regression.

RESULTS

Overall, 10651 kidney transplant recipients were included, of which 279 (2.6%) were elderly adults. The proportion of elderly recipients increased from 0.6 to 4.4% from 2000 to 2015. Compared with younger recipients, elderly recipients were more likely to receive kidneys from deceased donors, elderly donors, and expanded criteria donors. Elderly recipients experienced poorer patient survival with 1- and 5-year survival ranging from 96% to 97% and 79% to 81%, respectively, compared with 97% to 99% and 90% 95% in younger recipients, respectively. Elderly recipients experienced comparable rates of delayed graft function and, in living donor kidney recipients, lower rates of acute rejection.

CONCLUSIONS

Kidney transplantation in the elderly population is increasing. Although elderly recipients had inferior survival and graft outcomes, elderly recipients generally received poorer quality kidneys. The outcomes achieved in this cohort of elderly adults are encouraging, and improving elderly recipient outcomes should be an important focus for research.

Factors Influencing Long-Term Patient and Allograft Outcomes in Elderly Kidney Transplant Recipients

Introduction

Individuals aged ≥65 years are increasingly prevalent on the waitlist for kidney transplantation, yet evidence on recipient and donor factors that define optimal outcomes in elderly patients after kidney transplantation is scarce.

Methods

We used multivariable Cox regression modeling to determine the factors associated with all-cause death, death with a functioning graft, and overall and death-censored graft survival, using data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) registry.

Results

A total of 802 kidney transplant recipients aged ≥65 years underwent their first transplantation between June 2006 and December 2016. Median age at transplantation was 68 years (interquartile range = 66−69 years). The 1-year and 5-year overall patient and graft survivals (95% confidence interval [CI]) were 95.1 (93.5−96.7) and 79.0 (75.1−82.9), and 92.9 (91.1−94.7) and 75.4 (71.3−79.5), respectively. Factors associated with higher risks of all-cause death included prevalent coronary artery disease (adjusted hazard ratio [95% confidence interval] = 1.47 [1.03–2.11]), cerebrovascular disease (1.99 [1.26–3.16]), increasing graft ischemic time (1.06 per hour [1.03–1.09]), donor age (1.02 per year [1.01–1.03]), delayed graft function (1.64 [1.13−2.39]), and peritoneal dialysis pretransplantation (1.71 [1.17–2.51]).

Conclusion

Prevalent vascular disease and peritoneal dialysis as a pretransplantation dialysis modality are risk factors associated with poorer outcomes in transplant recipients aged ≥65 years. Careful selection and evaluation of potential candidates may improve graft and patient outcomes in older patients.

Influence of pretransplant class I and II non-donor-specific anti-HLA immunization on immunologic outcome and graft survival in kidney transplant recipients

BACKGROUND

Anti-HLA immunization determined by Panel Reactive Antibody (PRA) is known to have a negative impact on patient and graft survival. The predictive value of peak PRA (pPRA) on immunologic outcome, however, and the individual effects of anti-HLA class I and II antibodies remain uncertain.

METHODS

The influence of HLA immunization on immunologic outcome parameters and graft survival was investigated in 1150 adult patients without pretransplant donor-specific antibodies (DSA) and in a subgroup of elderly kidney recipients aged ≥ 65 (n = 264). Anti-HLA immunization was defined as a pPRA > 0%. We investigated the influence of class I and II pPRA by dividing all kidney recipients into four pPRA groups (0%, 1-20%, 21-80%, >80%).

RESULTS

Patients with non-donor-specific pretransplant anti-HLA immunization were at a higher risk for developing de novo DSA (49.9% vs. 18.7% p < 0.001), antibody mediated rejections (ABMR) (15.7% vs. 5.1%; p < 0.001), had a poorer death censored graft survival (69.2% vs. 86.2%; p < 0.001) and a higher decline of the calculated GFR. In elderly patients anti-HLA immunization only had a significant influence on the development of DSA (40.5% vs. 27.4%; p = 0.004). A multivariate model adjusted for all relevant factors revealed only class I but not class II pretransplant HLA immunization as a significant independent risk factor for de novo DSA, ABMR and death censored graft loss (HR 2.76, p < 0.001, HR 4.16, p < 0.001 and HR 2.07, p < 0.001, respectively).

CONCLUSION

Mainly non-donor-specific pretransplant HLA class I immunization is an independent risk factor for the development of de novo DSA, ABMR and graft loss.

Transplanting the Elderly: Mandatory Age- and Minimal Histocompatibility Matching

Worldwide over 40% of patients receiving renal replacement therapy (RRT) are aged 65 years or older, a number that is still increasing. Renal transplantation is the preferred RRT, providing substantial survival benefit over those remaining on dialysis, including the elderly. Only 3% of patients aged 65 years or older accepted on the waiting list actually received a kidney transplant offer within the Eurotransplant allocation region. To increase the chance for elderly to receive a timely kidney transplant, the Eurotransplant Senior Program was introduced. The ESP supports local allocation of older kidneys to older donors in order to decrease cold ischemia time, while disregarding former exchange principles based on matching for HLA antigens. As a consequence, more elderly received a kidney transplant and a relative higher incidence of acute rejection resulted in additional courses of high steroids and/or depleting antibody therapy. Since death with a functioning graft due to infections is the dominant reason of graft loss in elderly, more intense clinical immunosuppression to prevent or treat acute rejection is not a very attractive option. Therefore in elderly kidney transplant candidates, we advocate reintroduction of minimal histocompatibility criteria (i.e., HLA-DR matching) followed by age-matching with mandatory local/regional allocation to also facilitate short cold ischemia.

Risk Factors for Early Graft Failure and Death After Kidney Transplantation in Recipients Older Than 70 Years

INTRODUCTION

Although kidney transplantation carries a survival benefit compared with dialysis, mortality, especially the first year after transplantation, is high in recipients older than 70. The aim of this study was to evaluate early death and graft failure, and to determine the risk factors associated with these events in this specific population.

METHODS

All patients older than 70 years who received a kidney transplant between January 2000 and December 2014 in the North-West of France were included (n = 171). Baseline characteristics and outcomes after transplantation were studied. Kaplan-Meier analysis was performed to assess patient and graft survival, and Cox regression analysis to evaluate risk factors for graft failure and patient death.

RESULTS

The mean recipient age was 73.3 ± 2.5 years. Death-censored graft survival at 1, 3, and 5 years were 82.6%, 78.7%, and 75.4%, respectively. Patient survival at 1, 3, and 5 years was 90.1%, 82.5%, and 68.1%, respectively. One year after transplantation, 17 patients (9.9%) were dead, mainly from infectious (58.5%) or cardiovascular disease (29.4%). According to the Cox multivariate analysis, the independent risk factors for death or graft failure during the first year were arrhythmia (odds ratio [OR] 2.26; 95% confidence interval [CI] 1.08-4.8), left-ventricular ejection fraction (LVEF) under 56% (OR 2.38; 95% CI 1.18-4.83), human leucocyte antigen (HLA) antibodies (OR 2.1; 95% CI 1.04-4.2), deceased donor from cardiovascular cause (OR 5.18; 95% CI 1.22-6.3), and acute rejection (OR 2.77; 95% CI 1.2-6.3).

CONCLUSION

In kidney transplant recipients older than 70 years, cardiac evaluation and immunosuppression optimization seem to be crucial to improve short-term patient and graft survival.

Corticosteroid minimization in renal transplantation: Careful patient selection enables feasibility

AIM

To explore the benefits and harms of corticosteroid (CS) minimization following renal transplantation.

METHODS

CS minimization attempts to improve cardiovascular risk factors (hypertension, diabetes, dyslipidemia), to enhance growth in children, to ameliorate bone disease and to lead to better compliance with immunosuppressive agents. Nevertheless, any benefit must be carefully weighed against the reduction in net immunosuppression and the potential harm to renal allograft function and survival.

RESULTS

Complete CS avoidance or very early withdrawal (i.e., no CS after post-transplant day 7) seems to be associated with better outcomes in comparison with later withdrawal. However, an increased incidence of CS-sensitive acute rejection has been observed with all CS minimization strategies. Among the prerequisites for the safe application of CS minimization protocols are the administration of induction immunosuppression and the inclusion of calcineurin inhibitors in maintenance immunosuppression regimens.

CONCLUSION

Transplant recipients at low immunological risk (primary transplant, low panel reactive antibodies) are thought as optimal candidates for CS minimization. CS avoidance may also be undesirable in patients at risk for glomerulonephritis recurrence or with severe delayed graft function and prolonged cold ischemia time. Thus, CS minimization is not yet ready for implementation in the majority of transplant recipients.

Transplanting the elderly: Balancing aging with histocompatibility

Across the world, the proportions of senior citizens (i.e. those ≥65years) increase rapidly and are predicted to constitute over 25% of the general population by 2050. In 2012 already 48% of the population with end stage renal disease (ESRD) was aged 65years or older. Transplantation is considered the preferred treatment option for ESRD offering survival advantage over long-term dialysis in the majority of patients. Indeed, acceptable outcomes have been documented for selected patients over the age of 70years or even cases over 80years. The reality of organ scarcity and prolonged waiting times for a deceased donor kidney transplantation, however, indicate that at best 50% of the selected elderly may have realistic expectations to receive a timely transplant offer. By choice or medical selection, access to transplantation also decreases with increasing age. In order to expedite the chance for elderly to receive a kidney transplant dedicated allocation systems have been developed. These allocation systems, like the Eurotransplant Senior Program (ESP), support preferential local allocation of kidneys from older donors to older patients in order to match recipient and graft life while disregarding histocompatibility for HLA antigens. The consequence has been more acute rejection episodes and an increase in immunosuppressive load. In the elderly, the most common cause of graft loss is death with functioning graft and death from infectious diseases is one of the dominant causes. The Eurotransplant Senior DR-compatible Program (ESDP) was designed to further improve the perspective of successful transplantation in the elderly in terms of life and quality of life by re-introducing matching criteria for HLA-DR in the old-for-old algorithm.

Pharmacokinetics and pharmacodynamics of immunosuppressive drugs in elderly kidney transplant recipients

Elderly patients are a fast growing population among transplant recipients over the past decades. Both the innate and adaptive immune reactivity decrease with age, which is believed to contribute to the decreased incidence of acute rejection and increased infectious death rate in elderly transplant recipients. In contrast to recipient age, donor age is associated with a higher incidence of acute rejection. Pharmacokinetic studies in renal transplant recipients show that CNI troughs are >5% higher in elderly compared to younger patients given the same dose normalized by body weight. This may impact the starting dose of tacrolimus and cyclosporine. Possibly in elderly patients the intracellular (in lymphocyte) concentrations are relatively high in relation to the whole blood concentration, resulting in a stronger pharmacodynamic effect at the same whole blood trough concentration. For cyclosporine this has been shown, but it is not clear if the same is true for other immunosuppressive drugs. Pharmacodynamic studies have compared the inhibition of target enzymes, or more downstream effects of immunosuppressive drugs, in younger and older patients. Measurement of nuclear factor of activated T-cell (NFAT)-regulated gene expression (RGE), a pharmacodynamic read-out of CNI, is a promising biomarker of immunosuppression. Low levels of NFAT RGE are associated with increased risk of infection and non-melanoma skin cancer in elderly patients. Clinical trials to evaluate the safety and efficacy of immunosuppression regimens in this specific patient population, which is underrepresented in published trials, are lacking. More studies in elderly patients are needed to investigate the impact of age on the pharmacokinetics or pharmacodynamics of immunosuppressive drugs, and to decide on the optimal regimen and target levels for elderly transplant recipients.

Clinical Outcome of Elderly Kidney Transplant Recipients from Spousal Donors

INTRODUCTION

Patients aged 60 years and older stand for the fastest growing group of patients with end-stage renal disease worldwide, and the need for kidney transplants among this population is rising. In Japan, living donor kidney transplantation is mainly performed to deal with the severe shortage of deceased donors, and the number of spousal transplants is currently increasing.

PATIENTS AND METHODS

A total of 164 patients with ESRD underwent living donor kidney transplantation at our institution, of whom 21 patients aged 60 years and older had spousal kidney transplantation. ABO-incompatible kidney transplantation was performed in 5 of the 21 cases. We analyzed these recipients.

RESULTS

Patient and graft survival rates were 100%. The incidence of acute rejection was 23.8%. Eight patients experienced cytomegalovirus viremia, two patients experienced Pneumocystis jiroveci infection, and one experienced bacterial pneumonia. Two patients developed cancers and underwent curative operation after transplantation.

CONCLUSIONS

Elderly kidney transplantation from spousal donors is associated with age-related immune dysfunction, which may develop infections and malignancies and could be immunologically high risk due to the high rate of ABO-incompatibility and poor histocompatibility. An effort to minimize the adverse effect of immunosuppression and to reduce the risk of acute rejection may be needed for an excellent long-term outcome.

Recipient-related risk factors for graft failure and death in elderly kidney transplant recipients

BACKGROUND

Elderly patients with end-stage renal disease have become the fastest growing population of kidney transplant candidates in recent years. However, the risk factors associated with long-term outcomes in these patients remain unclear.

METHODS

We retrospectively analyzed 166 recipients aged 60 years or older who underwent primary deceased kidney transplantation between 2002 and 2013 in our center. The main outcomes included 1-, 3- and 5-year patient survival as well as overall and death-censored graft survival. The independent risk factors affecting graft and patient survival were analyzed using Cox regression analysis.

RESULTS

The 1-, 3-, 5-year death-censored graft survival rates were 93.6%, 89.4% and 83.6%, respectively. Based on the Cox multivariate analysis, panel reactive antibody (PRA)>5% [hazard ratio (HR) 4.295, 95% confidence interval (CI) 1.321-13.97], delayed graft function (HR 4.744, 95% CI 1.611-13.973) and acute rejection (HR 4.971, 95% CI 1.516-16.301) were independent risk factors for graft failure. The 1-, 3-, 5-year patient survival rates were 84.8%, 82.1% and 77.1%, respectively. Longer dialysis time (HR 1.011 for 1-month increase, 95% CI 1.002-1.020), graft loss (HR 3.501, 95% CI 1.559-7.865) and low-dose ganciclovir prophylaxis (1.5 g/d for 3 months) (HR 3.173, 95% CI 1.063-9.473) were risk factors associated with patient death.

CONCLUSIONS

The five-year results show an excellent graft and patient survival in elderly kidney transplant recipients aged ≥60 years. PRA>5%, delayed graft function, and acute rejection are risk factors for graft failure, while longer duration of dialysis, graft loss and low-dose ganciclovir prophylaxis are risk factors for mortality in elderly recipients. These factors represent potential targets for interventions aimed at improving graft and patient survival in elderly recipients.

Managing transplant rejection in the elderly: the benefits of less aggressive immunosuppressive regimens

Organ transplantation is increasingly common in the older population, particularly among end-stage renal disease patients. The outcomes of transplantation are often inferior in older people compared with younger recipients, partly because of the side effects of immunosuppressive medication used after organ transplantation. In this paper, we explore treatment considerations for older transplant patients. The current commonly used immunosuppressive protocols have not been validated sufficiently in older organ recipients. The primary objective for the management of transplant recipients of all ages is to prevent rejection without increasing the risk of infection or other long-term complications. To avoid serious side effects related to immunosuppressive treatment, the clinician should consider modifying and tailoring the long-term regimen for individual patients. Modifications for older recipients include reduction in the dosage or avoidance of calcineurin inhibitors, with or without the introduction of a mammalian target of rapamycin inhibitor and discontinuing the use of corticosteroids. Such modifications must consider the individual risks and needs of each recipient. Treatment of an acute rejection episode should follow the same protocol as for younger recipients, but special attention is needed to ensure reduction in the total immunosuppressive load. One way to achieve this is to avoid anti-thymocyte globulin (ATG) induction and to use on-demand ATG treatment of rejection on the basis of the patient's CD3 T cell count.

Kidney transplantation in the older adult

The end-stage renal disease population is aging. Nearly half of all new patients are older than 65 years and one third are older than 70 years. Assessing the possibility of transplantation for older patients with end-stage renal disease often involves contemplating more complex issues, including cognitive impairment, decreased functional status, and frailty, which makes selecting appropriate candidates more difficult. Older transplant recipients have decreased patient and transplant survival compared with younger recipients. For example, 75% of deceased donor transplant recipients aged 30-49 years are alive after 5 years compared to only 61% for those older than 65 years. Despite poorer outcomes compared with younger recipients, older transplant recipients have a significant improvement in survival compared with similar patients who remain on the wait list, with decreases in mortality of 41%-61% depending on the study. Use of living donors, even older living donors, provides significantly better outcomes for elderly recipients compared with the use of deceased donors. However, in the absence of a living donor, survival is improved significantly by accepting an expanded criteria donor organ rather than waiting for a standard criteria deceased donor. Older transplant recipients experience more infectious complications and less acute rejection, but the risk of transplant loss from rejection is increased compared with younger patients. These immunologic issues, along with the fact that older patients often are excluded from transplant trials, have made selecting an ideal immunosuppressive regimen challenging. Prospective comparative trials of different agents in the elderly population are warranted to better define the risk-benefit profile. This review discusses transplantation outcomes, including patient and transplant survival, different donor types, quality of life, and immunosuppression for older dialysis patients.

Solid-organ transplantation in older adults: current status and future research

An increasing number of patients older than 65 years are referred for and have access to organ transplantation, and an increasing number of older adults are donating organs. Although short-term outcomes are similar in older versus younger transplant recipients, older donor or recipient age is associated with inferior long-term outcomes. However, age is often a proxy for other factors that might predict poor outcomes more strongly and better identify patients at risk for adverse events. Approaches to transplantation in older adults vary across programs, but despite recent gains in access and the increased use of marginal organs, older patients remain less likely than other groups to receive a transplant, and those who do are highly selected. Moreover, few studies have addressed geriatric issues in transplant patient selection or management, or the implications on health span and disability when patients age to late life with a transplanted organ. This paper summarizes a recent trans-disciplinary workshop held by ASP, in collaboration with NHLBI, NIA, NIAID, NIDDK and AGS, to address issues related to kidney, liver, lung, or heart transplantation in older adults and to propose a research agenda in these areas.

Induction immunosuppressive therapy in the elderly kidney transplant recipient in the United States

BACKGROUND AND OBJECTIVES

The choice of induction agent in the elderly kidney transplant recipient is unclear.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The risks of rejection at 1 year, functional graft loss, and death by induction agent (IL2 receptor antibodies [IL2RA], alemtuzumab, and rabbit antithymocyte globulin [rATG]) were compared among five groups of elderly (≥60 years) deceased-donor kidney transplant recipients on the basis of recipient risk and donor risk using United Network of Organ Sharing data from 2003 to 2008.

RESULTS

In high-risk recipients with high-risk donors there was a higher risk of rejection and functional graft loss with IL2RA versus rATG. Among low-risk recipients with low-risk donors there was no difference in outcomes between IL2RA and rATG. In the two groups in which donor or recipient was high risk, there was a higher risk of rejection but not functional graft loss with IL2RA. Among low-risk recipients with high-risk donors, there was a trend toward a higher risk of death with IL2RA.

CONCLUSIONS

rATG may be preferable in high-risk recipients with high-risk donors and possibly low-risk recipients with high-risk donors. In the remaining groups, although rATG is associated with a lower risk of acute rejection, long-term outcomes do not appear to differ. Prospective comparison of these agents in an elderly cohort is warranted to compare the efficacy and adverse consequences of these agents to refine the use of induction immunosuppressive therapy in the elderly population.

Rabbit antithymocyte induction and dosing in deceased donor renal transplant recipients over 60 yr of age

BACKGROUND

Antithymocyte globulin (rATG) is a commonly used induction agent in renal transplantation; however, data in older kidney recipients are limited.

METHODS

We reviewed charts of 301 deceased donor renal transplants who received a protocol consisting of 3-7 doses of rATG and triple maintenance therapy. Outcomes of patients >60 yr of age (n = 45) were compared to those aged 18-59 yr (n = 256).

RESULTS

  Older recipients had more diabetics, were more likely to receive expanded criteria donor kidneys (p < 0.01), and over 30% were sensitized. Recipients >60 received less cumulative rATG (4.6 vs. 5.1 mg/kg; p < 0.01). Three-yr acute rejection was lower in the >60 group (2% vs. 16%, p < 0.01) although glomerular filtration rates were similar between groups. Actuarial graft survival was similar; however, patient survival in the >60 group at three yr was lower (80% vs. 95%; p = 0.02). Specifically, patients >60 with delayed graft function and rATG cumulative dosing >6 mg/kg had a survival of <50% by two yr.

CONCLUSION

Recipients over 60 yr receiving rATG induction have acceptable renal function and a low risk of rejection; however, reduced survival was noted among those receiving >6 mg/kg. These data suggest that when used, lower cumulative dosages of rATG are preferable in the older recipient.

Renal transplantation in the elderly: South Indian experience

In developing countries, renal transplantation is offered to young end-stage renal disease (ESRD) patients, while the older ones face limitations due to higher mortality risk. We retrospectively analyzed 225 patients who underwent renal transplantation from living donors, aged 40-60 years (Group A) and >60 years (Group B), focusing on their survival outcome. Group A (n = 181) had mean creatinine (mg/dL) 1.41 ± 0.84, 1.30 ± 0.65 and 1.40 ± 0.60 and mean eGFR (mL/min/1.73 m(2)) of 65.32 ± 23.03, 69.14 ± 32.65 and 59.21 ± 22.79 at 0, 3 and 6 months post-transplantation. Death-censored graft survival was 93.1% in first year followed by 91.2% in subsequent 4 years. Patient survival was 92.5% in first year, 90.7% in the next 2 years, and 89.2% in 4th year. Highest cumulative graft survival was 86.7% in the first year with 83.4%, 82.7% and 82.4% during the subsequent 3 years. Group B (n = 44) had mean creatinine (mg/dL) of 1.46 ± 1.02, 1.29 ± 0.23 and 1.2 ± 0.29 with a mean eGFR (mL/min/1.73 m(2)) of 67.90 ± 23.48, 67.02 ± 12.76 and 75.23 ± 15.19 at 0, 3 and 6 months. Highest death-censored graft survival was 97.4% in the first year with 94.7% in next 3 years. Patient survival was 88.1% throughout 4 years post-transplantation. Cumulative graft survival was 84.1% during 4 years. Biopsy-proven acute rejection rate was 28.7% in group A and 15.9% in group B (P = 0.058). There was higher mortality rate in group B with death mainly due to infections and cardiovascular complication. Cardiovascular risk assessment, pre-transplant cancer screening and judicious use of immunosuppressive agents should help minimize adverse events, balanced with an inherently reduced risk of acute rejection, hence the graft survival advantage and is the way forward to maximize patient and renal allograft survival in elderly patients.

The combination of donor and recipient age is critical in determining host immunoresponsiveness and renal transplant outcome

OBJECTIVE

To evaluate the interaction of donor and recipient age on transplant outcome and immune response.

SUMMARY BACKGROUND DATA

The age of donor and recipient is becoming increasingly important in organ transplantation. We tested the relevance and consequences of recipient and donor age on immunoresponsiveness and transplant outcome in a uni- and multilateral cohort analysis.

METHODS

We obtained and analyzed data from 108,188 recipients of deceased donor kidneys of the United Network for Organ Sharing database transplanted between 1995 and 2008. Univariate analysis of allograft and patient survival was calculated by Kaplan Meyer. Multivariate analyses were performed using the Cox Proportional Hazards method. Data were assessed and compared by decades of increasing donor and recipient age with and without censoring transplant loss for death with a functioning graft. This approach allowed a detailed analysis of interacting factors.

RESULTS

Transplant survival was lowest in elderly recipients. However, when the analysis was censored for patient's death with a functioning kidney transplant, survival improved incrementally with each decade of increasing recipient age. This was even more surprising as older recipients had received less well-matched organs of poorer quality. The frequency of acute rejection decreased dramatically with increasing age, emphasizing the effect of age on the vigor of the recipient's immune responses. In contrast, increasing donor age was associated with more frequent acute rejection rates. The effects of donor and recipient age in combination demonstrated that grafts of older donors fared significantly better in older recipients.

CONCLUSIONS

Our results show that increasing recipient age is associated with an improved transplant survival, lower rates of rejection, and superior outcome of older donor organs. Physiological and/or immunologic aspects of organ and recipient age seem to determine, at least in part, the success of renal transplantation.

Kidney transplantation in the elderly

There is an increase in the older incident end-stage renal disease population that is associated with an increasing prevalence of end-stage renal disease in the United States. This trend is paralleled by an increasing rate of kidney transplantation in the elderly. Although patient survival is lower in older versus younger kidney recipients, the elderly benefit from a reduction in mortality rate and improved quality of life with transplantation compared with dialysis. Immunologic, physiologic, and psychosocial factors influence transplant outcomes and should be recognized in the care of the elderly transplant patient. In this review, we discuss transplantation in the elderly patient, particularly the topics of access to transplantation, patient and graft survival, the impact of donor quality on transplant outcomes, immunology and immunosuppression of aging, and ethical considerations in the development of an equitable organ allocation scheme.

Immunosuppression in high-risk transplantation

PURPOSE OF REVIEW

Increasingly, transplant clinicians are faced with providing candidates with increased risks for poorer outcome with donor grafts that also carry higher risks of failure. Understanding the role of immunosuppressive management in these combinations of higher risks remains important for optimizing results.

RECENT FINDINGS

Few immunosuppressive protocols have been rigorously tested in the high-risk renal transplant setting. The two main risk categories accounted for in the trials are those ones that confer increased risks to renal function, usually carried by the donor organs, and those protocols defined by increased risk for immunological failure, mostly determined by recipient characteristics. The studied protocols generally involve reduction or avoidance of nephrotoxic drugs in the first case and use of lymphocyte-depleting agents in the case of increased immunological risk. In both scenarios, acceptable short-term results have been achieved. However, long-term results for high-risk transplants defined either by donor or recipient factors have yet to be reported.

SUMMARY

The lack of long-term data for optimizing the right immunosuppressive regimen for a given donor/recipient risk profile remains an ongoing challenge for researchers and clinicians alike.

Renal transplantation in the elderly

Elderly patients are increasingly being considered for kidney transplantation due to a global explosion of the aging population with end-stage renal disease (ESRD). However, mounting scarcity of available organs for transplant has led to a wider disparity between organ supply and demand. Consequently, the criteria for accepting kidneys for transplantation have been extended in an attempt to allow the use of organs from elderly donors or those with significant co-morbidities, so-called "expanded criteria donor" (ECD) kidneys. Excellent outcomes have been achieved from ECD kidneys with appropriate donor and recipient profiling and selection. With increasing recovery efforts directed at older donors, the concept of age-matching is becoming more accepted as a method of optimizing utilization of organs in elderly donors and recipients. Utilization of pulsatile perfusion has further improved ECD outcomes and helped the decision-making process for the UNOS (United Network for Organ Sharing) offer. However, age-related immune dysfunction and associated co-morbidities make the elderly transplant recipients ever more susceptible to complications associated with immunosuppressive agents. Consequently, the elderly population is at a higher risk to develop infections and malignancy in the post-transplant period notwithstanding improved transplant outcomes. Appropriate immunosuppressive agents and dosages should be selected to minimize adverse events while reducing the risk of acute rejections and maximizing patient and renal allograft survival.

Immunosuppression of the elderly kidney transplant recipient

The growing number of elderly patients with end-stage kidney disease awaiting transplantation has resulted in a corresponding rise in the number of elderly transplant recipients. In this paper, we review existing literature on age-related changes, transplant outcomes, and complications in the elderly in an attempt to propose a tailored approach to immunosuppression management in this group of patients. Despite the fact that the benefit of transplantation in the elderly is well established, clinical trials evaluating the safety and efficacy of immunosuppression regimens are lacking. Until such data exists, immunosuppression of the elderly transplant recipient should be based on the traditional principles which guide all transplant protocols and consideration of factors that are unique to the elderly. There are limited data regarding age-related changes in immune function and metabolism of immunosuppression agents in this population. Results of registry data analyses suggest that the risk of acute rejection decreases with age; however, the impact of acute rejection on long-term allograft function is greater in this population. There is also an increased risk of infection and adverse events posttransplantation among these patients. Elderly patients are more likely to receive organs from extended criteria donors and the impact of donor factors on transplant outcomes must therefore be considered. Taking these factors into consideration, we propose an approach to immunosuppression in the elderly based on individual risk stratification of treatment failure and the potential for adverse events.

Relapse rate and outcome of ANCA-associated small vessel vasculitis after transplantation

BACKGROUND

Anti-neutrophil cytoplasm antibody-associated systemic vasculitis (AASV) is a rare disease and frequently leads to end-stage renal disease (ESRD). Potentially fatal disease activity can develop after the onset of ESRD or in transplanted patients despite the immunosuppressive effects of uraemia and rejection prophylaxis, respectively, leading to concern that such patients may have greater morbidity and mortality.

METHODS

To assess the outcome of patients with AASV following kidney transplantation, a retrospective analysis was performed of nine patients with AASV at our unit who received renal transplants between 1987 and 2000. The renal survival of the patients was compared with a control population who received kidney transplants over the same period for causes other than AASV and diabetes mellitus.

RESULTS

Nine patients with the diagnosis of AASV (five patients with Wegener's granulomatosis and four with microscopic polyangiitis) received eight cadaveric grafts and one live-related graft after a mean of 44 months from the start of dialysis. These patients had a mean age of 49.2 years at time of transplantation and they were followed up for a mean of 62 months post-transplantation. Two patients with Wegener's granulomatosis suffered a vasculitic relapse affecting the upper respiratory tract at 40 and 50 months post-transplantation, corresponding to a relapse rate of 0.04 per patient per year. The renal transplant function of vasculitis patients compared with 18 non-diabetic control patients who were transplanted at the same time was better in the vasculitis patients at some time points (P=0.054 at 6 months).

CONCLUSIONS

There is a substantial relapse rate in the AASV population, especially affecting the upper respiratory tract and with increasing duration of follow-up. Nonetheless, renal transplantation is a good option for the treatment of vasculitis patients and their outcome compares favourably with that of other non-diabetic patients following transplantation.