Sensitivity of expanded-criteria donor kidneys to cold ischaemia time.

UNLABELLED: The United Network for Organ Sharing (UNOS), working in conjunction with organ procurement organizations and transplant programmes, has recently defined a class of cadaver kidney grafts for special allocation procedures to enhance utilization of those organs. The criteria defining these expanded-criteria donor (ECD) kidneys are donor age > or = 60 yr or donor age between 50 and 59 yr plus two of the following characteristics: donor history of cerebrovascular accident (CVA), donor history of hypertension (htn), and elevated creatinine (>1.5) at any time during donor management. Kidney grafts from ECD donors carry an increased relative risk of non-function compared to other cadaver kidney grafts. The goal of the special allocation procedure is to reduce the time associated with placement by matching ECD grafts with patients previously designated as being willing to accept them. In assessing the potential impact of these allocation procedures, the sensitivity of ECD grafts to cold ischaemia time (CIT) became of great significance. Specifically, we questioned whether minimization of CIT might reduce the relative risk of poor graft function, justifying reduction of the geographical range of placement and thereby reducing the time the grafts would spend in-transit. METHODS: To assess this, we queried the SEOPF database for cadaveric kidney transplants between 1/1/1997 and 15/8/2002. There were 1312 transplants from ECD donors during this period and 8451 from non-ECD donors. Between these groups, there were no significant differences in recipient gender, ethnicity, peak and most recent panel reactive antibody (PRA). Recipients of ECD kidneys were significantly older: 50.9 +/- 13.0 yr vs. 44.9 +/- 13.9 (mean age +/- SD, P < 0.0001). There were statistically significant but very small differences in the degree of AB and DR mismatch between the groups. RESULTS: Defining delayed graft function (DGF) as dialysis within the first week post-transplant and primary non-function (PNF) as dialysis within the first week and failure in the first year, we found an association with CIT as illustrated in Table 1. Overall, ECD kidneys had a significantly increased (P < 0.0001) incidence of PNF and DGF. Notably, PNF in ECD appeared to be uniformly distributed across CIT and while DGF was CIT-dependent, the DGF differences between ECD and non-ECD were fairly consistent across CIT. CONCLUSION: While CIT minimization is potentially beneficial, ECD kidneys do not appear to be more sensitive to it than non-ECD kidneys.

Impact of acute rejection episodes on long-term graft survival following simultaneous kidney-pancreas transplantation.

Although it is well established that acute rejection is one of the major risk factors for chronic graft loss following kidney transplantation, its effect on long-term graft survival following simultaneous kidney-pancreas transplants (SKPTs) is less well known. We analyzed a large cohort of SKPTs and cadaver kidney transplants reported to the United Network for Organ Sharing database during 1988-97, to determine the impact of acute rejection episodes on long-term kidney and pancreas graft survival. Only patients whose kidney and pancreas grafts had survived for at least 1 year were included. Other potential risk factors influencing long-term graft survival were included in the analysis. Of the 4251 SKPTs, 45% had no acute rejection, 36% had kidney only rejection, 3% had pancreas only rejection, and 16% had both kidney and pancreas rejection within the 1st year post transplant. The 5-year kidney and pancreas graft survival rates adjusted for other risk factors were 91% and 85%, respectively; for those with no acute rejection episodes, 88% and 84%, respectively; for those with kidney only rejection, 94% and 83%, respectively; for those with pancreas only rejection; and 86% and 78%, respectively, for those with both kidney and pancreas rejection. The relative risk (RR) of kidney graft failure was 1.32 when acute rejection involved the kidney graft only, while the RR was 1.53 when the rejection involved both organs. We conclude that acute rejection episodes have a negative impact on the long-term kidney graft survival in the SKPT population similar to that in the cadaver kidney transplant population. Patients who had acute rejection episodes of both kidney and pancreas have the worst long-term graft survival.

Long-term survival following simultaneous kidney-pancreas transplantation versus kidney transplantation alone in patients with type 1 diabetes mellitus and renal failure.

BACKGROUND: Pancreas transplantation improves quality of life and prevents the progression of secondary complications of diabetes. Whether these benefits translate into a long-term survival advantage is not entirely clear. METHODS: Using the United Network for Organ Sharing database, we analyzed long-term survival in 18,549 patients with type 1 diabetes and renal failure who received a kidney transplant between 1987 and 1996. Patient survival was calculated using the Kaplan-Meier method. Proportional hazards models were used to adjust for effects of differences in recipient and donor variables between simultaneous kidney-pancreas transplants (SKPTs) and kidney-alone transplants. RESULTS: SKPT and living donor kidney recipients had a significant crude survival distribution advantage over cadaver kidney transplant recipients (8-year survival rates: 72% for SKPT recipients, 72% for living donor kidney recipients, and 55% for cadaver kidney recipients). The survival advantage for SKPT recipients over cadaver kidney recipients diminished, but persisted after adjusting for donor and recipient variables and kidney graft function as time-varying covariates. SKPT recipients had a high mortality risk relative to living donor kidney recipients through 18 months posttransplantation (hazards ratio, 2.2; P < 0.001), but had a lower relative risk (hazard ratio, 0.86; P < 0.02) thereafter. In SKPT recipients, maintenance of a functioning pancreas graft was associated with a survival benefit. CONCLUSION: The long-term survival of SKPT recipients is superior to that of cadaver kidney transplant recipients with type 1 diabetes. There is no difference in survival of SKPT recipients and living donor kidney recipients with type 1 diabetes at up to 8 years' follow-up; the former have a greater early mortality risk and the latter have a greater late mortality risk. Results of this study suggest that successful simultaneous kidney-pancreas transplantation is not only life enhancing, but life saving.

Transplantation of pediatric en bloc cadaver kidneys into adult recipients: a single-center experience.

Faced with an extreme shortage of organs transplant professionals continue to explore various strategies to expand the donor pool. Transplantation of kidneys from older and very young donors are two such options. Although kidneys from young donors (less than 5 years of age) have been associated with a high rate of technical complications and suboptimal results, use of these kidneys en bloc has been advocated to improve the outcomes. We reviewed our experience with en bloc kidney transplantation at the University of Kentucky over the past 10 years. Between 1991 and 2000 ten patients underwent kidney transplantation using kidneys en bloc from donors <5 years age. The mean age of the donors was 2.8 years with a mean weight of 16 kg (range 13-21). Mean age of the recipients was 42 years. One patient lost the graft on day one from venous thrombosis. One patient lost the graft 7 years post-transplant from chronic rejection. All of the remaining patients are doing well with functioning grafts (mean follow-up 4.5 years; range 6 months to 10 years). Both one-year and five-year graft survival rates are 89 per cent. The present study confirms that excellent results can be achieved with kidney transplantation using kidney transplantation using kidneys en bloc from donors younger than 5 years of age.