Survival in recipients of marginal cadaveric donor kidneys compared with other recipients and wait-listed transplant candidates

Access to Quality: Evaluation of the Allocation of Deceased Donor Kidneys for Transplantation

Disparities in both access to the kidney transplant waiting list and waiting times for transplant candidates have been extensively documented with regard to ethnicity, gender, socioeconomic factors, and region. However, the issue of access to equivalent quality organs has garnered less attention. The principal aim of this study was to determine whether certain patient populations were more likely to receive lower quality organs. This was a retrospective cohort study of all deceased-donor adult renal transplant recipients in the United States from 1996 to 2002 (n = 45,832). Using previously reported categorization of donor quality (I to V), the propensity of transplant recipients to receive lower-quality kidneys in a cumulative logit model was evaluated. Older patients were progressively more likely to receive lower-quality organs (age > or = 65 yr, odds ratio [OR] = 2.1, P < 0.01) relative to recipients aged 18 to 24 yr. African American and Asian recipients had a greater likelihood of receiving lower-quality organs relative to non-Hispanic Caucasians. Regional allocation networks were highly variable with regard to donor quality. Neither recipient gender (OR = 1.00, P = 0.81) nor patient's primary diagnosis were associated with donor quality. Findings suggest that disparities in the quality of deceased donor kidneys to transplant recipients exist among certain patient groups that have previously documented access barriers. The extent to which these disparities are in line with broad policies of equity and potentially modifiable will have to be examined in the context of allocation policy.

EAU guidelines on renal transplantation

OBJECTIVES

To produce a guidelines text, on behalf of the European Association of Urology, providing insights in the issues surrounding renal transplantation.

METHOD

A group of international experts in renal transplantation carried out a non-structured literature review on available medical databases and urological literature.

RESULT

A guideline text is presented providing an overview of key issues involved in the patients' management such as assessment of donors, pre-transplant evaluation, techniques, management, post-transplant care, etc.

CONCLUSION

The current text represents a consensus statement developed by a group of international experts in renal transplantation.

Modifiable factors predicting patient survival in elderly kidney transplant recipients

BACKGROUND

Elderly transplant candidates represent an increasingly important group on the waiting list for kidney transplantation. Yet the factors that determine posttransplantation outcomes in this population remain poorly defined.

METHODS

We performed a population-based retrospective cohort study involving all patients aged 60 years or older who received a first cadaveric kidney transplantation between 1985 and 2000 in the province of Quebec. The main outcomes were patient survival, overall graft survival, and treatment failure (patient death or graft loss within the first posttransplant year). Survival analyses were performed using a Cox proportional hazard model. Logistic regression identified factors predicting treatment failure.

RESULTS

On multivariate analysis, the modifiable factors associated with patient survival were active smoking at transplantation [hazard ratio (HR) 2.09, 95% confidence interval (CI) 1.22-3.60)], body mass index (BMI) (HR 1.34 for a 5-point increase, 95% CI 1.05-1.67), and time on dialysis before transplantation (HR 1.10 for a 1-year increase, 95% CI 1.02-1.18). The only modifiable factor associated with graft survival was active smoking at transplantation (HR 2.04, 95% CI 1.24-3.30). Treatment failure was associated with time on dialysis before transplantation (odds ratio for dialysis >/=2 years 3.28, 95% CI 1.34-7.9).

CONCLUSION

Our results show that active smoking, obesity, and time on dialysis before transplantation are modifiable risk factors associated with an increased risk of mortality after transplantation in elderly recipients. They represent potential targets for interventions aimed at improving patient and graft survival in elderly patients.

Hypertension in Kidney Transplantation

Arterial hypertension in renal transplant patients plays a major role in the progression to chronic allograft failure, and in morbidity and mortality associated with cardiovascular disease. Its cause is diverse, with contributions not only from donor and/or recipient factors, but it also is influenced strongly by the type of immunosuppressive regimen. Despite increased awareness of the adverse effects of hypertension in both graft and patient survival, long-term studies have shown that arterial hypertension in the transplant population has not been controlled adequately. Ambulatory blood pressure measurements provide the advantage of a better assessment of the diurnal blood pressure variation, a predictor of target organ damage and cardiovascular morbidity and mortality events. Although the available data do not support the recommendation of any class of antihypertensive medication as preferred agents for blood pressure management in the transplant population, angiotensin-converting enzyme inhibitors and angiotensin-receptor blockers have shown beneficial effects beyond their antihypertensive effects. Clinical data in transplant recipients are emerging that suggest that applying interventions proven to be effective in reducing cardiovascular morbidity and mortality in the general population may be effective for the transplant population.

Do Elderly Patients Deserve a Kidney Graft?

PURPOSE

Compare renal transplant long-term outcomes among recipients aged 60 years or older with those in younger patients.

PATIENTS AND METHODS

We analyzed 103 transplants in recipients above 60 years of age for the influence of key factors related to the graft and patient. The results were compared with 1060 transplant recipients aged 18 to 59 years.

RESULTS

The mean ages were 62.93 and 40.35 years for the older and younger group. The older group showed a higher prevalence of obesity and unknown etiologies for the end-stage renal disease. Important comorbidity was significantly more frequent among recipients aged more than 60 years, mainly of a cardiovascular nature (56% vs 18.5%). Donor age (39.75 vs 31.59 years), cold ischemia time (22.43 vs 20.49 hours) and human leukocyte antigen compatibilities (2.59 vs 2.36) were significantly greater in the older subset. After a mean follow-up of 4.72 and 6.07 years for the older versus younger group, we found no differences in initial graft function, acute rejection rate, and serum creatinine/clearance. Patient and graft survivals at 1, 5, and 10 years were lower among the 60+ group. There were no differences in graft survival censored for death with a functioning graft, namely, 95.1%, 89.4%, and 81.2% for the 60+ cohort. The main cause of graft loss in the older group was death with a functioning graft.

CONCLUSION

Renal transplantation should be considered for selected patients older than 60 years. Despite a shorter life expectancy, they benefit from it similar to younger recipients.

Kidney Transplantation From Cadaveric Donors Unsuitable for Other Centers and Older Than 60 Years of Age

INTRODUCTION

The demand for kidney transplants and the improvement in recipient outcomes over the last years have stimulated surgeons to expand the criteria for usable donor organs, by accepting older patients to expand their donor pool. We herein report our experience with kidney transplants from donors aged older than 60 years, who have been declined by other transplantation centers.

PATIENTS AND METHODS

Sixty kidney transplantations were performed with grafts procured from donors aged older than 60 years. Forty-five patients received a single kidney graft (SKG) and 15 received a dual kidney graft (DKG). Mean donor age was 62 years for SKG and 64 years for DKG. Double kidney transplantations were performed with the ipsilateral allocation of both grafts.

RESULTS

No primary graft nonfunction occurred. Delayed graft function was observed in 22 SKG (48.8%) and in 7 DKG (46.6%). Acute rejection rates were 9% for SKG and 0% for DKG. One-year patient survival rates were 95% and 100% for SKG and DKG, respectively. Mean serum creatinine levels at 1-year posttransplantation were 1.9 mg/dL for SKG and 1.3 mg/dL for DKG. There were no surgical postoperative complications and mortality. Death censored 1-year graft survival rate was 88% for SKG and 94% for DKG.

CONCLUSIONS

Our experience with marginal donors who have been declined by other transplantation centers has demonstrated that such organs, with accurate selection criteria, could be safely allocated to elderly recipients with no increase in postoperative complications, guaranteeing satisfactory results in the short and medium term, allowing a significant improvement in the number of transplants.

Kidney transplantation and wait-listing rates from the international Dialysis Outcomes and Practice Patterns Study (DOPPS)

BACKGROUND

The international Dialysis Outcomes and Practice Patterns Study (DOPPS I and II) allows description of variations in kidney transplantation and wait-listing from nationally representative samples of 18- to 65-year-old hemodialysis patients. The present study examines the health status and socioeconomic characteristics of United States patients, the role of for-profit versus not-for-profit status of dialysis facilities, and the likelihood of transplant wait-listing and transplantation rates.

METHODS

Analyses of transplantation rates were based on 5267 randomly selected DOPPS I patients in dialysis units in the United States, Europe, and Japan who received chronic hemodialysis therapy for at least 90 days in 2000. Left-truncated Cox regression was used to assess time to kidney transplantation. Logistic regression determined the odds of being transplant wait-listed for a cross-section of 1323 hemodialysis patients in the United States in 2000. Furthermore, kidney transplant wait-listing was determined in 12 countries from cross-sectional samples of DOPPS II hemodialysis patients in 2002 to 2003 (N= 4274).

RESULTS

Transplantation rates varied widely, from very low in Japan to 25-fold higher in the United States and 75-fold higher in Spain (both P values <0.0001). Factors associated with higher rates of transplantation included younger age, nonblack race, less comorbidity, fewer years on dialysis, higher income, and higher education levels. The likelihood of being wait-listed showed wide variation internationally and by United States region but not by for-profit dialysis unit status within the United States.

CONCLUSION

DOPPS I and II confirmed large variations in kidney transplantation rates by country, even after adjusting for differences in case mix. Facility size and, in the United States, profit status, were not associated with varying transplantation rates. International results consistently showed higher transplantation rates for younger, healthier, better-educated, and higher income patients.

Steroid avoidance in renal transplantation using basiliximab induction, cyclosporine-based immunosuppression and protocol biopsies

BACKGROUND

Reducing chronic steroid exposure is important to minimize steroid-related morbidity, particularly for susceptible renal transplant recipients. Steroid-free and steroid-sparing protocols have shown benefits, but safety has not been established for all populations. We investigated the safety of steroid avoidance (SA) in a population including African-Americans, using modern immunosuppression with protocol biopsy monitoring.

METHODS

A randomized-controlled SA trial (early discontinuation, days 2-7) was conducted in a population (n = 77) including African-Americans and cadaveric kidney recipients. Patients received basiliximab, cyclosporine (CsA), and mycophenolate mofetil (MMF). In controls, steroids were tapered to 5 mg prednisone/d by day 30. Protocol biopsies were performed (1, 6, 12 and 24 months) to evaluate subclinical acute rejection (SCAR) and chronic allograft nephropathy (CAN).

RESULTS

The SA did not result in significantly higher incidences of graft loss, AR, SCAR, CAN, or renal fibrosis. SA patients experienced similar renal function, comparable serum lipid levels, and a trend toward fewer cases of new-onset diabetes. Clinical outcomes of African-American and non-African-American patients did not significantly differ.

CONCLUSIONS

The SA is safe in the context of basiliximab induction and CsA-based immunosuppression. This protocol could minimize steroid-related side effects in susceptible groups, including African-Americans, without increasing the risk of AR or graft failure.

United Network for Organ Sharing's expanded criteria donors: is stratification useful?*

The United Network for Organ Sharing (UNOS) Expanded Criteria Donor (ECD) system utilizes pre-transplant variables to identify deceased donor kidneys with an increased risk of graft loss. The aim of this study was to compare the ECD system with a quantitative approach, the deceased donor score (DDS), in predicting outcome after kidney transplantation. We retrospectively reviewed 49 111 deceased donor renal transplants from the UNOS database between 1984 and 2002. DDS: 0-39 points; >or=20 points defined as marginal. Recipient outcome variables were analyzed by ANOVA or Kaplan-Meier method. There was a 90% agreement between the DDS and ECD systems as predictors of renal function and graft survival. However, DDS identified ECD- kidneys (10.7%) with a significantly poorer outcome than expected (DDS 20-29 points, n = 5,252). Stratification of ECD+ kidneys identified a group with the poorest outcome (DDS >or=30 points). Predictability of early post-transplant events (i.e. need for hemodialysis, decline of serum creatinine and length of hospital stay) was also improved by DDS. DDS predicted outcome of deceased donor renal transplantation better than the ECD system. Knowledge obtained by stratification of deceased donor kidneys can allow for improved utilization of marginal kidneys which is not achieved by the UNOS ECD definition alone.

Impact of the Expanded Criteria Donor Allocation System on the Use of Expanded Criteria Donor Kidneys

BACKGROUND

The U.S. Organ Procurement and Transplantation Network recently implemented a policy allocating expanded criteria donor (ECD) kidneys by waiting time alone. ECD kidneys were defined as having a risk of graft failure > or = 1.7 times that of ideal donors. ECDs include any donor > or = 60 years old and donors 50 to 59 years old with at least two of the following: terminal creatinine >1.5 mg/dL, history of hypertension, or death by cerebrovascular accident. The impact of this policy on use of ECD kidneys is assessed.

METHODS

The authors compared use of ECD kidneys recovered in the 18 months immediately before and after policy implementation. Differences were tested using t test and chi2 analyses.

RESULTS

There was an 18.3% increase in ECD kidney recoveries and a 15.0% increase in ECD kidney transplants in the first 18 months after policy implementation. ECD kidneys made up 22.1% of all recovered kidneys and 16.8% of all transplants, compared with 18.8% (P<0.001) and 14.5% (P<0.001), respectively, in the prior period. The discard rate was unchanged. The median relative risk (RR) for graft failure for transplanted ECD kidneys was 2.07 versus 1.99 in the prepolicy period (P=not significant); the median RR for procured ECD kidneys was unchanged at 2.16. The percentage of transplanted ECD kidneys with cold ischemia times (CIT) <12 hr increased significantly; the corresponding percentage for CIT > or = 24 hr decreased significantly.

CONCLUSIONS

The recent increase in ECD kidney recoveries and transplants appears to be related to implementation of the ECD allocation system.

Effect of Delayed Graft Function in Hypersensitized Kidney Transplant Recipients

There is increased evidence about the deleterious effect of delayed graft function (DGF) in both short- and long-term kidney graft outcome. Among the mechanisms involved in the production of DGF, immune factors play a role, especially in the level of hypersensitization. From the 1389 patients transplanted at our hospital until November 2004, it has been found that the presence of moderate and high levels of sensitization, as measured by panel-reactive antibodies, is a risk factor for suffering from DGF. Further, DGF was associated with poor graft survival, and the risk was even higher when DGF was combined with moderate/high panel-reactive antibodies. Recent data demonstrate the usefulness of intravenous immunoglobulins in the management of hypersensitized patients in terms of short-term outcome. It remains to be demonstrated whether this therapy is able to ameliorate the higher ischemic injury that kidneys undergo from these immunologically high-risk patients.

Quantifying organ donation rates by donation service area

Previous measures of OPO performance based on population counts have been deemed inadequate, and the need for new methods has been widely accepted. This article explains recent developments in OPO performance evaluation methodology, including those developed by the SRTR. As a replacement for the previously established measure of OPO performance--donors per million population--using eligible deaths as a national metric has yielded promising results for understanding variations in donation rates among the donation service areas assigned to each OPO. A major improvement uses "notifiable deaths" as a denominator describing a standardized maximal pool of potential donors. Notifiable deaths are defined as in-hospital deaths among ages 70 years and under, excluding certain diagnosis codes related to infections, cancers, etc. A most proximal denominator for determining donation rates is "eligible deaths," which includes only those deaths meeting the criteria for organ donation upon initial assessment. Neither measure is based on the population of a geographic unit, but on restricted upper limits of deaths that could be potential donors in any one locale (e.g., hospital or OPO). The inherent strengths and weaknesses of metrics such as donors per eligible deaths, donors per notifiable deaths, and number of organs per donor are discussed in detail.

The broad spectrum of quality in deceased donor kidneys

The quality of the deceased donor organ clearly is one of the most crucial factors in determining graft survival and function in recipients of a kidney transplant. There has been considerable effort made towards evaluating these organs culminating in an amendment to allocation policy with the introduction of the expanded criteria donor (ECD) policy. Our study, from first solitary adult deceased donor transplant recipients from 1996 to 2002 in the National Scientific Transplant Registry database, presents a donor kidney risk grade based on significant donor characteristics, donor-recipient matches and cold ischemia time, generated directly from their risk for graft loss. We investigated the impact of our donor risk grade in a naive cohort on short- and long-term graft survival, as well as in subgroups of the population. The projected half-lives for overall graft survival in recipients by donor risk grade were I (10.7 years), II (10.0 years), III (7.9 years), IV (5.7 years) and V (4.5 years). This study indicates that there is great variability in the quality of deceased donor kidneys and that the assessment of risk might be enhanced by this scoring system as compared to the simple two-tiered system of the current ECD classification.

Hypertension, antihypertensive agents and outcomes following renal transplantation

Hypertension is common following renal transplantation and adversely affects graft and patient survival. However, strategies for antihypertensive drug therapy and target blood pressure have not been clearly defined.

AIM

To assess the influence of achieved blood pressure and antihypertension drug therapy on graft and patient survival with the aim of identifying targets and event rates for future intervention studies.

METHODS

We undertook a longitudinal follow up study of 634 renal transplant patients. Patients were surveyed in December 1994 and followed up after 102 months. Blood pressure (BP) was determined from the mean of three clinic readings and antihypertensive drug therapy recorded.

RESULTS

Complete follow up data were available for analysis on 622 patients (57.2% male; mean age: 45.2 +/- 13.0 yr. There were 158 (25.4%) deaths and 115 (18.5%) death-censored graft failures. Lower systolic and diastolic blood pressure were associated with better graft survival in the Kaplan-Meier analysis. Univariate analysis showed serum creatinine (HR 1.012, p < 0.001), duration of renal replacement therapy (HR 0.946, p = 0.012), age (HR 0.979, p = 0.014) and pulse pressure (HR 1.017, p = 0.044) to be predictors of graft survival with serum creatinine and duration of renal replacement therapy as the only significant factors in the multivariate analysis. Lower systolic and pulse pressure were associated with better patient survival in the Kaplan-Meier analysis. Age (HR) 1.062, p < 0.0001), serum creatinine (HR 1.002, p = 0.021), diabetes (HR 3.371, p < 0.0001), and pulse pressure (HR 1.013, p = 0.036) were significant predictors of patient survival in the univariate and multivariate analysis. Patient survival was reduced with increasing number of antihypertensives (p < 0.05), as was graft survival (p < 0.05). Reduced patient and graft survival were seen in patients prescribed calcium channel antagonists (p < 0.01). There was no increased patient mortality in those patients on beta-blockers or angiotensin converting enzyme (ACE) inhibitors.

CONCLUSION

Hypertension is a risk factor, which remains despite the use of anti-hypertensives, for reduced patient and graft survival. The risk was not significant when blood pressure was entered together with serum creatinine in the multivariate analysis. Beta-blockers may have a beneficial effect on cardiovascular mortality, and ACE inhibitors a beneficial effect on both patient and graft survival. There is a pressing need for interventional studies to assess the impact of blood pressure targets on patient and graft survival and the effect of individual agents on these outcomes.

Predictors of cardiovascular events and associated mortality within two years of kidney transplantation

BACKGROUND

Cardiovascular disease is the most common cause of death after renal transplantation. Furthermore, acute coronary syndrome (ACS) attributable to coronary artery disease (CAD) accounts for the majority of deaths due to cardiovascular disease posttransplant. While renal transplantation is the treatment of choice for end-stage renal disease, understanding the causes of graft and patient loss is exceedingly important to improve outcomes.

METHODS

This observational case-controlled study included 780 patients who underwent a kidney transplant between 1989 and 2001 who experienced early ACS (within 2 years). Patients were compared with controls matched for gender, year of transplant, and age. The primary outcome was the occurrence of an ACS event within 2 years after renal transplantation.

RESULTS

Cardiovascular disease was the most common cause of death, with all 13 cardiovascular deaths due to CAD. An additional 15 episodes of nonfatal ACS episodes occurred. Thirty-seven percent of early ACS occurred perioperatively, the majority in the first 3 posttransplant months. On multivariate analysis, diabetes (OR [odds ratio] 5.56; P = .0007), smoking (OR 3.56; P = .034), and prior transplant (OR 2.81; P = .047) were associated with early ACS.

CONCLUSIONS

Diabetes, smoking, and prior transplant were significantly associated with early ACS. The majority of events occurred perioperatively or within 3 months of transplant, highlighting the importance of improved screening and perioperative management.

Immunosuppressive drug monitoring - what to use in clinical practice today to improve renal graft outcome

Therapeutic drug monitoring (TDM) of immunosuppressive therapy is becoming an increasingly complex matter as the number of compounds and their respective combinations are continuously expanding. Unfortunately, in clinical practice, monitoring predose trough blood concentrations is often not sufficient for guiding optimal long-term dosing of these drugs. The excellent short-term results obtained nowadays in renal transplantation confer a misleading feeling of safety despite the fact that long-term results have not substantially improved, definitely not to a point where longer graft survival could counteract the increasing need for transplant organs and less toxicity and side-effects could ameliorate patient survival. It is therefore a challenging task to try to tailor immunosuppressive drug therapy to the individual patient profile and this in a time-dependent manner. For the majority of currently used immunosuppressive drugs, measurement of total drug exposure by determination of the dose-interval area under the concentration curve (AUC) seems to provide more useful information for clinicians in terms of concentration-exposure and exposure-response as well as reproducibility. To simplify this laborious way of measuring drug exposure, several validated abbreviated AUC profiles, accurately predicting the dose-interval AUC, have been put forward. Together with an increasing knowledge of the time-related pharmacokinetic behaviour of immunosuppressive drug and their metabolites, studies are focusing on how to apply abbreviated AUC sampling methods in clinical transplantation, taking into account the numerous factors affecting drug pharmacokinetics. Eventually, TDM using abbreviated AUC profiles has to be prospectively tested against classic methods of drug monitoring in terms of cost-effectiveness, feasibility and clinical relevance with the ultimate goal of improving patient and graft survival.

Expanded-criteria donor kidneys: a single-center clinical and short-term financial analysis--cause for concern in retransplantation

BACKGROUND

Expanded-criteria donor (ECD) kidneys are associated with a higher risk of posttransplant failure, but they remain a favorable alternative to dialysis. Now that a uniform definition of "expanded criteria" exists, it is more appropriate than ever to evaluate their utility compared with that seen with non-ECD kidneys.

METHODS

The authors analyzed 202 cadaveric kidney-only recipients that underwent transplantation from January 1999 to September 2001, including 45 (22%) recipients whose donors met current ECD criteria.

RESULTS

ECD and non-ECD kidney recipients had similar pretransplant characteristics except for older age and increased duration of renal failure in the ECD group. Patient, graft, and death-censored graft survival in both groups were similar in primary recipients but significantly worse in retransplant recipients of ECD kidneys. The relative risk of death-censored graft loss was 1.58 in the ECD group (P = 0.45). Overall inpatient charges (minus organ acquisition charge) for 1 year posttransplant were 76,962 US dollars (ECD) versus 71,026 US dollars (non-ECD) (P = 0.53); the same charges in retransplant recipients were 136,596 US dollars (ECD) versus 91,296 US dollars (non-ECD) (P = 0.25). ECD recipients, especially retransplant recipients, had consistently higher creatinine concentrations, although the average current value of all functioning ECD grafts remains less than 2 mg/dL. ECD recipients had a higher incidence of ureteral stricture (4.4% vs. 0%), but this never resulted in graft loss.

CONCLUSIONS

Considering the widening disparity between renal allograft availability and need and the fact that ECD kidneys provide superior outcomes compared with dialysis, the authors' data encourage the continued use of ECD kidneys in primary recipients but justify caution in the retransplant setting.

Effect of immunosuppressive agents on long-term survival of renal transplant recipients: focus on the cardiovascular risk

In the control of acute rejection, attention is being focused more and more on the long-term adverse effects of the immunosuppressive agents used. Since cardiovascular disease is the main cause of death in renal transplant recipients, optimal control of cardiovascular risk factors is essential in the long-term management of these patients. Unfortunately, several commonly used immunosuppressive drugs interfere with the cardiovascular system. In this review, the cardiovascular adverse effects of the immunosuppressive agents currently used for maintenance immunosuppression are thoroughly discussed. Optimising immunosuppression means finding a balance between efficacy and safety. Corticosteroids induce endothelial dysfunction, hypertension, hyperlipidaemia and diabetes mellitus, and impair fibrinolysis. The use of corticosteroids in transplant recipients is undesirable, not only because of their cardiovascular effects, but also because they induce such adverse effects as osteoporosis, obesity, and atrophy of the skin and vessel wall. Calcineurin inhibitors are the most powerful agents for maintenance immunosuppression. The calcineurin inhibitor ciclosporin (cyclosporine) not only induces these same adverse effects as corticosteroids but is also nephrotoxic. Tacrolimus has a more favourable cardiovascular risk profile than ciclosporin and is also less nephrotoxic. It has little or no effect on blood pressure and serum lipids; however, its diabetogenic effect is more prominent in the period immediately following transplantation, although at maintenance dosages, the diabetogenic effect appears to be comparable to that of ciclosporin. The diabetogenic effect of tacrolimus can be managed by reducing the dose of tacrolimus and early corticosteroid withdrawal. The effect of tacrolimus on endothelial function has not been completely elucidated. The proliferation inhibitors azathioprine and mycophenolate mofetil (MMF) have little effect on the cardiovascular system. Yet, indirectly, by inducing anaemia, they may lead to left ventricular hypertrophy. MMF is an attractive alternative to azathioprine because of its higher potency and possibly lower risk of malignancies. Sirolimus also induces anaemia, but may be promising because of its antiproliferative features. Whether the hyperlipidaemia induced by sirolimus counteracts its beneficial effects is, as yet, unknown. It may be combined with MMF, however, initial attempts resulted in severe mouth ulcers.

ABO-incompatible kidney transplantation

When a renal transplant candidate's only medically-acceptable living kidney donor is ABO incompatible, the most common practice is to place them on the deceased donor list. Over the past few years, the implementation of paired kidney donor exchange programs and the development of protocols to overcome the ABO blood group barrier have become much more successful and widespread. Here we review the therapeutic options for patients whose only living kidney donor is ABO incompatible, with a specific emphasis on the rationale for and the current outcomes of ABO incompatible living donor kidney transplantation.

Dual-kidney transplantation with organs from expanded criteria donors: a long-term follow-up

BACKGROUND

Since 1995, dual-kidney transplantation using organs from marginal donors has been used at our center to expand the organ donor pool and decrease the waiting time for deceased donor kidney transplantation. This approach has allowed for a shorter waiting period without compromising outcome in the early posttransplant period. We now have 8-year follow-up in the first recipients. Older individuals were offered this option preferentially, because we reasoned that they would stand to benefit most from the shorter waiting period.

METHODS

Patients aged 55 years or more who underwent either dual-kidney transplantation with expanded criteria donors or single-kidney transplantation with standard donors were included in this study. All expanded criteria donor organs were those that were refused by all other local transplant centers. The primary endpoints were recipient death and graft failure.

RESULTS

Waiting time for dual-kidney transplantation was 440 +/- 38 days versus 664 +/- 51 days for single-kidney transplantation (P<0.01). The 8-year actuarial patient survivals for the single- and dual-kidney transplants were 74.1% and 82.1%, respectively. The 8-year actuarial graft survivals for the single- and dual-kidney transplants were 59.4% and 69.7%, respectively.

CONCLUSIONS

Eight-year actuarial patient and graft survivals in older individuals who underwent dual-kidney transplantation are equivalent to those who underwent standard single-kidney transplantation. With the continuing organ shortage and increasing waiting times for cadaver kidney transplantation, dual-kidney transplantation using organs that would otherwise be discarded offers a good option for older individuals who may not withstand a long waiting period.

Kidney transplantation: the evolving challenges

Kidney transplantation is the treatment of choice for patients with end stage renal disease. Kidney transplantation not only improves the quality of life but also prolongs life. Over the last decade, the short-term allograft survival rate has been improved dramatically. Chronic allograft nephropathy and death from cardiovascular diseases become predominant causes of later graft loss. Prevention and treatment of these disease processes require a comprehensive approach. The ever-increasing shortage of organ supply becomes the greatest challenge for the transplant community and modern medicine. More and more patients are waiting for organs; many of them are dying while waiting. Xenotransplantation and organ engineering and cloning are promising techniques and can potentially provide organs for transplantation in the future.

Kidney transplantation: recent developments and recommendations for anesthetic management

Kidney transplantation is the treatment of choice for patients with end-stage renal disease. After receiving a transplant, survival rates are higher and comorbidities may resolve. As a consequence, more patients with significant comorbidities such as advanced cardiovascular disease will present for transplantation. This review highlights commonly encountered issues in patients undergoing kidney transplantation and recommendations are made for their anesthetic management.

The case for living kidney sales: rationale, objections and concerns

Currently, potential kidney transplant candidates are dying on the waiting list. One potential solution would be a regulated system of living kidney sales (with safeguards to protect the vendor). Potential objections and practical concerns are discussed.

The impact of transplantation with deceased donor hepatitis c-positive kidneys on survival in wait-listed long-term dialysis patients

Whether transplantation of deceased donor kidney allografts from donors with antibodies against hepatitis C virus (HCV) confers a survival advantage compared with remaining on the kidney transplant waiting list is not yet known. We studied 38,270 USRDS Medicare beneficiaries awaiting kidney transplantation who presented with end-stage renal disease from April 1, 1995 to July 31, 2000. Cox regression was used to compare the adjusted hazard ratios for death among recipients of kidneys from deceased donors, and donors with antibodies against hepatitis C (DHCV+), controlling for demographics and comorbidities. In comparison to staying on the waiting list, transplantation from DHCV+ was associated with improved survival among all patients (adjusted hazard ratio for death 0.76, 95% CI 0.60, 0.96). Of patients receiving DHCV+ kidneys, 52% were themselves hepatitis C antibody positive (HCV+), so outcomes associated with use of these grafts may have particular implications for HCV+ transplant candidates. Recommendations for use of DHCV+ kidneys may require analysis of data not currently collected from either dialysis or transplant patients. However, transplantation of DHCV+ kidneys is associated with improved patient survival compared to remaining wait-listed and dialysis dependent.

Kidney transplantation from marginal donors

AIM

The increasing demand for transplantation and the shortage of available organs limit the success of organ transplant programs. The use of marginal donors to expand the donor pool is receiving increased attention. We reviewed a 28-month experience of kidney transplants from marginal donors to assess the impact on patient and graft survival.

PATIENTS AND METHODS

From January 2001 to May 2003, 78 kidney transplants were performed, including 50 grafts from cadaver donors and 28 from living donors with 3 patients receiving a double kidney transplant. The patients were divided into 4 groups: 31 patients received a kidney from an ideal cadaver donor (group 1a); 19 patients received a graft from a marginal cadaver donor (group 1b); 19 patients received an ideal living related kidney (group 2a); and 9 patients received a marginal living kidney graft (group 2b).

RESULTS

Twenty-eight grafts from marginal donors were transplanted with an average follow-up of 16 months (range, 1-28 months). The graft survival rates for groups 1a, 1b, 2a, and 2b were 93%, 79%, 100%, and 100% and patient survival rates were 96%, 89%, 100%, and 100%, respectively.

CONCLUSION

Despite the observation that use of marginal donors has been associated with a worse outcome compared with ideal donors, we of such grafts resulted in improved quality of life and survival expectancy compared with maintenance dialysis. The marginal kidney donors represent a feasible way to improve the donor pool.

Can the outcome of older donor kidneys in transplantation be predicted? An analysis of existing scoring systems

The use of older cadaveric donors in kidney transplantation is increasing. The transplant outcome of the single older kidney is generally inferior prompting some to recommend dual kidney transplantation. The ability to predict the outcome of the solitary marginal kidney becomes clinically important. Such insight might allow for better allocation strategies that would minimize poorer outcomes while permitting optimal rationalization of this scarce resource. A retrospective, single center review of 79 single kidney transplants from 50 donors aged > or =55 yr was performed. We tested the validity of published scoring strategies to predict subsequent recipient kidney function. Receiver operating characteristic curve analysis was used to quantify the donor strategies separating good and poor outcomes based upon recipient creatinine clearance (CrCl) <30 mL/min. Two pre-transplant donor assessment strategies, Nyberg score and donor CrCl (dCrCl) were found to predict subsequent kidney function in recipients. When Nyberg variables (cold ischemia time, donor diabetes and hypertension status, incremental donor age >55 yr and cause of death) in conjunction with the dCrCl were considered, they were no better than dCrCl alone. Although dCrCl had a reasonable negative predictive ability, the positive predictive value was <50%. Our analysis suggests that a dCrCl of > or =70 mL/min is a better discriminator of subsequent kidney function outcomes than a dCrCl of 90 mL/min as recommended by the Dual Transplant Registry.

Late calcineurin inhibitor withdrawal as a strategy to prevent graft loss in patients with suboptimal kidney transplant function

Chronic allograft nephropathy is a major cause of progressive renal failure in renal transplant recipients. Its etiology is multifactorial and may include both immunologic and nonimmunologic causes. In this observational cohort study we set out to see if calcineurin inhibitor withdrawal would reduce the likelihood of graft loss.

METHODS

One hundred and five renal transplant recipients with impaired kidney function (mean serum creatinine 3.0 +/- 0.1 mg/dl) and biopsy-proven chronic allograft nephropathy had the dose of their calcineurin inhibitors, cyclosporine (CSA), or tacrolimus (FK), reduced or discontinued with either the addition of, or continuation of mycophenolate mofetil and low-dose corticosteroids. This intervention occurred at a mean of 29.0 +/- 2.7 months after transplantation. Follow-up after intervention was 54.3 +/- 4.1 months in the reduced CSA group (n = 64), 41.6 +/- 3.2 months in the reduced FK group (n = 28), and 75.5 +/- 6.7 months in the calcineurin inhibitor withdrawal group (n = 13).

RESULTS

There were 24 graft failures in the reduced CSA group, 9 graft failures in the reduced FK group, and 1 graft lost in the calcineurin inhibitor withdrawal group. The unadjusted relative risk for graft failure in the CSA and FK groups combined (confidence interval 1.05-31.6), was 4.07 using the calcineurin inhibitor withdrawal group as the reference, p = 0.05. A Cox proportional hazards model adjusting for baseline covariates including age, gender, race, type of transplant, delayed graft function, baseline blood pressure and random serum glucose and cholesterol demonstrated that only calcineurin inhibitor dose reduction but not withdrawal, older age, delayed graft function, higher serum creatinine at the time of intervention, and higher diastolic blood pressure and serum glucose, correlated with graft loss. Only 6 of the 105 patients developed Banff grade acute rejection. All responded to steroid therapy. We conclude that although this observational cohort study may have a selection bias, late calcineurin inhibitor withdrawal in patients with chronic allograft nephropathy and impaired kidney function appears safe and durable as a treatment strategy to reduce the likelihood of graft failure.

Reasons for non-use of recovered kidneys: the effect of donor glomerulosclerosis and creatinine clearance on graft survival

BACKGROUND

In 2000, the United Network for Organ Sharing/Organ Procurement and Transplantation Network Registry reported 540 recovered kidneys were discarded because of biopsy results, and 210 were discarded because of poor organ function. We compared the percentage of glomerulosclerosis (GS) and creatinine clearance (CrCl) of both discarded and transplanted cadaveric kidneys and examined their effect on graft survival and function.

METHODS

The cohort consisted of all cadaveric kidneys (n= 3,444) with reported biopsy results between October 25, 1999 and December 31, 2001. Graft survival was calculated by univariate and multivariate models.

RESULTS

Fifty-one percent of discarded kidneys had GS of less than 20%, 27% had a CrCl greater than 80 mL/min, and 15% (129 kidneys) had both GS less than 20% and a CrCl of greater than 80 mL/min. Univariate analyses of kidneys with less than or equal to 20% GS revealed no difference in 1-year graft survival when the CrCl was greater than or less than or equal to 80 mL/min. When GS was greater than 20%, 1-year graft survival of kidneys with a CrCl of greater than 80 mL/min was significantly greater than that of kidneys with a CrCl of less than or equal to 80 mL/min. Multivariate results showed no significant difference in relative risk of graft loss with GS greater than 20% versus less than or equal to 20% when the CrCl was either 50 or 80 mL/min. With both GS less than or equal to 20% and greater than 20%, serum creatinine at 1 year was significantly lower in kidneys with CrCl greater 80 mL/min.

CONCLUSIONS

Calculated donor CrCl does, and percentage GS on donor kidney biopsies does not, correlate well with 1-year graft survival and function, and percentage GS should not be used as the sole criterion for discarding recovered cadaveric kidneys.

Increased kidney transplantation utilizing expanded criteria deceased organ donors with results comparable to standard criteria donor transplant

OBJECTIVE

To compare outcomes in recipients of expanded criteria donor (ECD) versus standard criteria donor (SCD) kidneys at a single center using a standardized approach with similar immunosuppression.

SUMMARY BACKGROUND DATA

Expanded criteria deceased organ donors (ECD) are a source of kidneys that permit more patients to benefit from transplantation. ECD is defined as all deceased donors older than 60 years and donors older than 50 years with 2 of the following: hypertension, stroke as the cause of death, or pre-retrieval serum creatinine (SCr) greater than 1.5 mg/dl.

METHODS

We retrospectively studied 90 recipients of adult deceased donor kidneys transplanted from October 1, 2001 to February 17, 2003, including 37 (41%) from ECDs and 53 (59%) from SCDs. ECD kidneys were used by matching estimated renal functional mass to recipient need, including the use of dual kidney transplants (n = 7). ECD kidney recipients were further selected on the basis of older age, HLA-matching, low allosensitization, and low body mass index. All patients received a similar immunosuppressive regimen. Minimum follow up was 9 months.

RESULTS

There were significant differences in donor and recipient characteristics between ECD and SCD transplants. Patient (99%) and kidney graft survival (88%) rates and morbidity were similar between the 2 groups, with a mean follow-up of 16 months. Initial graft function and the mean 1-week and 1-, 3-, 6-, 12-, and 18-month SCr levels were similar among groups.

CONCLUSIONS

The use of ECD kidneys at our center effectively doubled our transplant volume within 1 year. A systematic approach to ECD kidneys based on nephron mass matching and nephron sparing measures may provide optimal utilization with short-term outcomes and renal function comparable to SCD kidneys.

Morbid obesity is not a contraindication to kidney transplantation

BACKGROUND

Concern that morbidly obese (body mass index [BMI] 35) kidney transplant recipients have worse outcomes than non-morbidly obese recipients leads many transplant centers to deny them the benefit of kidney transplantation. These concerns are supported by guidelines recently published by the American Society of Transplantation. However, successfully transplanted morbidly obese persons have a survival advantage over those that remain on dialysis. It is our practice to evaluate morbidly obese transplant candidates for transplantation under the same criteria used for nonobese candidates. This report reviews our experience with morbidly obese kidney transplant recipients having a three year follow-up.

METHODS

Outcomes for 23 morbidly obese (BMI 35, range 37 to 56) kidney transplant recipients transplanted between January 1995 and February 2000 were compared with 224 nonobese (BMI 25) kidney recipients transplanted during the same period.

RESULTS

Patient and graft survivals were similar between both groups. Although 3-year graft survival for morbidly obese recipients of cadaver organs was 75% compared with 90% for the nonobese group, this finding was not statistically significant, and 3-year graft survival was 100% for morbidly obese recipients of living donor organs compared with 91% for nonobese recipients. Morbidly obese recipients had significantly longer hospital stays, higher readmission rates, and a higher wound infection rate than nonobese recipients.

CONCLUSIONS

We found that morbidly obese persons have 3-year graft and patient survivals similar to nonobese persons. Although they also have greater complications and greater numbers of days in the hospital, we believe these reasons are not sufficient to deny morbidly obese persons the survival and quality-of-life advantages of kidney transplantation.

Hepatitis C and renal transplantation in the era of modern immunosuppression

Kidneys from donors who are positive for hepatitis C virus (DHCV+) have recently been identified as an independent risk factor for mortality after renal transplantation. However, it has not been determined whether risk persists after adjustment for baseline cardiac comorbidity or applies in the era of modern immunosuppression. Therefore, a historical cohort study was conducted of US adult cadaveric renal transplant recipients from January 1, 1996, to May 31, 2001; followed until October 31, 2001. A total of 36,956 patients had valid donor and recipient HCV serology. Cox regression analysis was used to model adjusted hazard ratios for mortality and graft loss, respectively, adjusted for other factors, including comorbid conditions from Center for Medicare and Medicaid Studies Form 2728 and previous dialysis access-related complications. It was found that DHCV+ was independently associated with an increased risk of mortality (adjusted hazard ratio, 2.12, 95% confidence interval, 1.72 to 2.87; P < 0.001), primarily as a result of infection. Mycophenolate mofetil was associated with improved survival in DHCV+ patients, primarily related to fewer infectious deaths. Adjusted analyses limited to recipients who were HCV+, HCV negative, or age 65 and over, or by use of mycophenolate mofetil confirmed that DHCV+ was independently associated with mortality in each subgroup. It is concluded that DHCV+ is independently associated with an increased risk of mortality after renal transplantation adjusted for baseline comorbid conditions in all subgroups. Recipients of DHCV+ organs should be considered at high risk for excessive immunosuppression.

MEASUREMENT OF CHRONIC DAMAGE IN THE DONOR KIDNEY AND GRAFT SURVIVAL

BACKGROUND

So-called marginal kidneys are used increasingly in renal transplantation, but features of marginal kidneys are disputed.

METHODS

To help define marginal, a morphometric measure, the index of chronic damage, was applied retrospectively to 500 implantation biopsy specimens of cadaveric grafts, and death-censored graft survival was calculated, up to 14 years after transplantation.

RESULTS

An index of 0% (n=242) was associated with better survival than 1%, with little difference between 1% and 39% (n=249). An index of 40% or more (n=9) was associated with the worst survival (chi=14.2, 2 df, P <0.001). After controlling for donor age, the only values of the index related to survival were 40% and above (hazard ratio, 2.96; P =0.01). Donor age group 10 to 39 years old (n=238) had better survival than 1 to 9 years old (n=26) and 40 to 73 years old (n=236) (hazard ratios, 2.83 and 2.06, respectively; P <0.001). An early episode of acute rejection affected survival even at 6 years and later after transplantation (hazard ratio, 1.94; P <0.04).

CONCLUSIONS

Marginal kidneys are identified using the index of chronic damage, but they are so rare that measurement is not necessary on every graft. After routine graft allocation and in the absence of acute rejection, a kidney from virtually any donor in an age group has the same potential as a graft from nearly all others in that group.

Genome-wide gene-expression patterns of donor kidney biopsies distinguish primary allograft function

Roughly 25% of cadaveric, but rarely living donor renal transplant recipients, develop postischemic acute renal failure, which is a main risk factor for reduced long-term allograft survival. An accurate prediction of recipients at risk for ARF is not possible on the basis of donor kidney morphology or donor/recipient demographics. We determined the genome-wide gene-expression pattern using cDNA microarrays in three groups of 36 donor kidney wedge biopsies: living donor kidneys with primary function, cadaveric donor kidneys with primary function and cadaveric donor kidneys with biopsy proven acute renal failure. The descriptive genes were characterized in gene ontology terms to determine their functional role. The validation of microarray experiments was performed by real-time PCR. We retrieved 132 genes after maxT adjustment for multiple testing that significantly separated living from cadaveric kidneys, and 48 genes that classified the donor kidneys according to their post-transplant course. The main functional roles of these genes are cell communication, apoptosis and inflammation. In particular, members of the complement cascade were activated in cadaveric, but not in living donor kidneys. Thus, suppression of inflammation in the cadaveric donor might be a cheap and promising intervention for postischemic acute renal failure.

A pilot protocol of a calcineurin-inhibitor free regimen for kidney transplant recipients of marginal donor kidneys or with delayed graft function

The worsening shortage of cadaver donor kidneys has prompted use of expanded or marginal donor kidneys (MDK), i.e. older age or donor history of hypertension or diabetes. MDK may be especially susceptible to calcineurin-inhibitor (CI) mediated vasoconstriction and nephrotoxicity. Similarly, early use of CI in patients with delayed graft function may prolong ischaemic injury. We developed a CI-free protocol of antibody induction, sirolimus, mycophenolate mofetil, and prednisone in recipients with MDK or DGF.

METHODS

Adult renal transplant recipients who received MDK or had DGF were treated with a CI-free protocol consisting of antibody induction (basiliximab or thymoglobulin), sirolimus, mycophenolate mofetil, and prednisone. Serial biopsies were performed for persistent DGF. Patients were followed prospectively with the primary endpoints being patient and graft survival, biopsy-proven acute rejection, and sirolimus-related toxicity.

RESULTS

Nineteen recipients were treated. Mean follow-up was 294 days. Actuarial 6- and 12-month patient survival was 100% and 100% and graft survival was 93% and 93%, respectively. The only graft loss was due to primary non-function (PNF). The incidence of AR was 16%. Mean serum creatinine at last follow-up was 1.6 mg/dL. Sirolimus-related toxicity included lymphocele (1), wound infection (2), thrombocytopenia (1). and interstitial pneumonitis (1).

CONCLUSION

A CI-free protocol with antibody induction and sirolimus results in low rates of AR and PNF and excellent early patient and graft survival in patients with MDK and DGF. CI-free protocols may allow expansion of the kidney donor pool by encouraging utilization of MDK at high risk for DGF or CI-mediated nephrotoxicity.

Increasing the donor pool using en bloc pediatric kidneys for transplant

OBJECTIVES

En bloc pediatric kidney transplants (EBPKT) are still a subject of controversy. The aim of this study was to determine whether acceptable long-term graft survival and function can be achieved in EBPKT compared with the transplant of single, cadaveric, adult donor kidneys.

METHODS

A retrospective review was conducted of 66 recipients of en bloc kidneys from cadaveric pediatric donors and 434 patients who underwent transplantation with a single kidney from an adult donor between January 1990 and May 2002 at the authors' hospital. The recipients were well-matched demographically. Both transplant groups were analyzed for short- and long-term performance in terms of transplant outcome and quality of graft function.

RESULTS

Overall death-censored actuarial graft survival rates at 1 and 5 years were 89.2% and 84.6% in the adult kidney transplants (AKT) and 83.3% and 81.1% in EBPKT, respectively (P=0.56). In the EBPKT group, graft function was improved over that observed in AKT. Vascular thrombosis was the most common cause of graft loss in EBPKT. Acute rejection occurred more frequently in AKT and Cox's regression analysis indicated that undergoing an AKT was a predictive factor for acute vascular rejection (adjusted risk ratio, 3.8; 95% confidence interval, 1.4-10.2; P=0.001).

CONCLUSIONS

Overall graft survival was similar in both groups, vascular complications were the main cause of graft loss in EBPKT, and the EBPKT showed excellent long-term graft function and a low incidence of acute rejection.

Allocation of deceased donor kidneys: past, present, and future

The manner in which deceased donor kidneys are allocated has broad relevance to the care of patients with end-stage renal disease. An algorithm governing the allocation of deceased donor kidneys has been applied in the United States since 1987. Adjustments were made to facilitate the national sharing of highly matched kidneys, but the main components of the algorithm remained largely unchanged. In ensuing years, the number of patients on the waiting list has increased steadily while the supply of kidneys has remained constant. The waiting time for an organ now is measured in years, and the allocation of organs has become unpredictable. As of October 2002, several important changes have been made to the algorithm. These changes are designed to increase the relative number of minority patients who undergo transplantation and the use of extended-criteria donor kidneys. They also have practical implications for the management of patients on the waiting list. The rationale behind these changes is discussed in the context of the ethical underpinnings of kidney allocation.

Expanding the donor pool: can the Spanish model work in the United States?

Since the creation of the Organizacion Nacional de Trasplantes (ONT) in 1989, the organ donation rate in Spain has doubled. Although often attributed to improved donor recruitment efforts, this increase may also represent higher utilization of marginal donors. Therefore, age-related donor recruitment in Spain and the US was evaluated. Data from the ONT, the US Scientific Registry of Transplant Recipients (SRTR), the US Census Bureau, and the Tempus databank of Spain's Instituto Nacional de Estadistica (INE) were analyzed. Between 1989 and 1999, the number of donors in Spain increased from 14.3 to 33.7 per million population (pmp; 136% increase) compared with an increase in the US from 16.2 to 21.5 donors pmp (33%). The largest difference between Spain and the US in the increased number of donors was in the 45-year-old group, representing 30.3% of donors in Spain in 1999 (44 donors pmp). If the US increased its older donor rates to match Spain's, an incremental 1235 donors per year would be realized. The high Spanish organ donation rates are largely attributable to increased use of older donors. Utilizing similar proportions of older donors in the US would increase the donor pool by almost 40%.

Optimizing cadaveric organ procurement: the catalan and Spanish experience

The need to face the increasing gap between the supply and the demand of transplants has led to the development of a permanent network of trained medical staff responsible for the organ donation and removal process in all centers accredited for that process. In Spain, this activity received a specific budget, like any other medical activity in hospitals, and the responsible staff became accountable for performance. This system dramatically increased the number of potential donors referred, not only young donors with trauma, but also elderly donors dying from stroke. The effect was that the donation rate increased by more than 100% in 10 years (from 14 to 34 donors per million population). Consequently, so did all the transplant figures. In some areas, such as Catalonia, it has been demonstrated that sustained kidney transplant activity of over 60 procedures per million population can maintain or slightly decrease the waiting list, despite increasing incidence and prevalence of end-stage renal failure. Quality monitoring of the donation and retrieval process shows that there are still opportunities for improvement if all potential donors are referred and all technical problems are overcome. Living donation and nonheart beating organ retrieval should also be promoted.

Conversion from cyclosporine to azathioprine at three months reduces the incidence of chronic allograft nephropathy

BACKGROUND

Conversion from cyclosporine to azathioprine after renal transplantation has been shown to be beneficial in terms of allograft function, cardiovascular risk factor profile, and the incidence of gout. A higher incidence of acute rejection, however, has also been reported and uncertainty still exists about the long-term outcome after conversion. We report on the extended follow-up of an open-label, randomized trial that examined conversion to azathioprine as early as three months after transplantation.

METHODS

One hundred twenty-eight patients were enrolled in this single-center study. Three months after transplantation they were randomly assigned to continue cyclosporine treatment (N = 68), or they were converted to azathioprine (N = 60). The steroid dose was temporarily increased in the patients who were converted.

RESULTS

Patient survival was not different in the two groups. Graft survival tended to be lower (64.7% vs. 76.5% at 15 years) in the cyclosporine continuation group (P = 0.14) when data were analyzed on an intention to treat basis. The graft survival of the patients that stayed on their assigned treatment was significantly higher in the azathioprine arm, starting at two years' post-transplantation. The glomerular filtration rate was significantly higher in the patients who were converted to azathioprine. More allograft biopsies were taken from patients remaining on cyclosporine for suspicion of cyclosporine-related nephrotoxicity and prompted a high rate of late conversions (19%). The relative risk of chronic allograft nephropathy was significantly higher in the group that continued cyclosporine [relative risk, 4.3 (95% CI, 1.4 to 12.9); P = 0.009]. Conversion to azathioprine reduced the need of blood pressure and lipid-lowering drugs.

CONCLUSION

Conversion to a calcineurin inhibitor-free immunosuppressive regiment three months after renal transplantation improved allograft function, reduced the need of cardiovascular risk factor-controlling medication, and reduced the incidence of chronic allograft nephropathy.

Impaired tubulointerstitial expression of endothelin-1 and nitric oxide isoforms in donor kidney biopsies with postischemic acute renal failure

BACKGROUND

About 30% of cadaveric renal allografts, but almost never living-donor kidneys, develop postischemic acute renal-transplant failure (ARF). We therefore quantified the expression of essential reperfusion regulators in different compartments of cadaveric and living-donor kidney biopsies.

METHODS

Specimens were obtained from donor kidneys at the end of the cold ischemia time before implantation and categorized into three groups according to donor source and early posttransplant function. Ten living-donor biopsies (LIV) were compared with nine cadaveric kidney biopsies (CAD) with primary posttransplant function (CAD-PF) and to nine with ARF (CAD-ARF). Laser capture microdissection was used to isolate glomeruli from tubulointerstitium. The gene expression of intercellular adhesion molecule (ICAM)-1, interleukin (IL)-1beta, endothelin (ET)-1, inducible nitric oxide synthase (iNOS), and endothelial nitric oxide synthase (eNOS) was quantified in glomeruli and tubulointerstitium by real-time polymerase chain reaction (TaqMan).

RESULTS

Tubulointerstitial areas of all CAD kidneys revealed significantly lower mRNA levels of all investigated genes compared with LIV. Tubulointerstitial ET-1, iNOS, and eNOS in CAD-ARF averaged only half of the expression in CAD-PF kidneys. ICAM-1 and IL-1beta mRNA concentrations were equal in CAD-PF and CAD-ARF. Glomerular expression of the investigated genes was equal in CAD and LIV kidneys with the exception of ICAM-1 and ET-1, which were two times higher in CAD-PF compared with LIV and CAD-ARF.

CONCLUSION

These data suggest that CAD compared with LIV kidneys have an impaired expression of immune and vasoregulatory genes in the tubulointerstitium, which may represent reduced cellular vitality and capacity to adaptation. The observed further reduction of ET-1, iNOS, and eNOS expression in CAD-ARF might contribute to reperfusion injury and delayed allograft function.