Establishing a composite tissue allograft registry.

Currently there is no international registry for composite tissue allografts (CTA), but there have been discussions about creating such a registry. This article discusses the advantages/benefits, and disadvantages of establishing an international composite tissue registry. It also looks at some of the potential pitfalls that may hinder the long-term survival of the effort and makes recommendations as to how to avoid them based on the experience of other registries. It is our belief that now is the time for the formation of a CTA registry. There is a strong consensus among the transplanting centers for its formation. If properly constructed, a scientific registry on CTA will be a true attribute to the scientific and medical communities.

The high-grade match program of the South-Eastern Organ Procurement Foundation: status at four years.

In summary, the HGM program is a voluntary, multicenter, prospective study of the SEOPF that is open to all transplant centers. The program extends mandatory sharing beyond the UNOS zero-antigen mismatch obligation, and uses preliminary crossmatching via ROP trays to try to facilitate transplantation of the highly sensitized patient. The program encompasses less than 7% of the cadaver kidney transplant activity of the participating centers, so it does not impact the majority of recipients. After 49 months of operation, it has significantly improved access to transplantation for blood group O patients, patients awaiting re-grafts, and those who are highly sensitized (PRA > or = 40%). Additionally, 92% of the HGM recipients have received an allograft with 2 or less antigens mismatched. Enrollment will continue until there is sufficient power to test the null hypothesis of equality of HGM and non-HGM transplants.

Effect of race on outcome following kidney and kidney-pancreas transplantation in type I diabetics: the South-Eastern Organ Procurement Foundation experience.

In this study we analyze the South-Eastern Organ Procurement Foundation (SEOPF) experience with kidney and kidney-pancreas transplantation in IDDM recipients and evaluate the impact of racial disparity on patient and graft outcome. Data obtained from 4413 kidney-alone and 884 pancreas transplants performed in White and Black type I diabetics at member institutions of SEOPF between 10/1/87 and 7/25/96 were analyzed. Survival data from 15,827 transplants performed during the same period of time in non-diabetics were available for comparison. A lesser proportion of pancreas recipients were Black compared to kidney-alone (12% vs 23%, p < 0.0005). Recipient race had no effect on patient survival in any of the groups studied. Kidney graft survival, on the other hand, was adversely affected by Black race in both non-diabetic and diabetic recipients of a kidney transplant but not in diabetics who received a combined pancreas-kidney transplant. As was the case for patient survival in diabetics, recipient race had no effect on pancreas graft survival. Cox Regression analysis showed that kidney-pancreas transplant (p = 0.034, RR = 0.49) and female recipient gender (p = 0.046, RR = 0.68) were associated with a lower risk of failure of the pancreas graft. The following factors were independent predictors of kidney graft outcome: Donor age (p = 0.0001, RR = 0.95), kidney-pancreas transplant (p = 0.0004, RR = 0.58), AB match (p = 0.001, RR = 0.86), DR match (p = 0.006, RR = 0.82), preservation time (p = 0.012, RR = 1.01), Black recipient race (p = 0.047, RR = 1.23) and living donor (p = 0.06, RR = 0.73). Our findings suggest that the effect of race on graft outcome observed in non-diabetic and, to a lesser extent, diabetic kidney-alone transplant recipients, is not present after kidney-pancreas transplantation.

Hepatitis antigenemia and survival after renal transplantation.

Some transplant programs regard hepatitis B antigenemia (HBsAg+) as a contraindication to renal transplantation. We studied the records of 13,287 renal transplant recipients, 781 (5.88%) who were positive for HBsAg, the remainder negative (HBsAg-). Patient survival for HBsAg-recipients is 91.8% at 1 year, 80.6% at 5 years, and 65.8% at 10 years. Patient survival for HBsAg+ recipients was 88.8% at 1 year, 77.6% at 5 years, and 61.6% at 10 years. The difference in patient survival was 3-4%, and graft survival was nearly constant at 3%. The statistical significance for patient survival was p = 0.02 by the log-rank test and p = 0.007 by the Wilcoxon test. There is far more statistical power (p = 0.0001) in other risk factors such as transplant number, recipient race, recipient age, and diabetes. Currently available diagnostic studies may allow better risk stratification of HBsAg+ candidates. We believe that hepatitis antigenemia without added and related risk factors has only a mild effect on graft and patient outcome.

The high grade match kidney sharing algorithm of the South-Eastern Organ Procurement Foundation (SEOPF): altering recipient demographics through improved matching.

BACKGROUND: Studies of kidneys shared through the South-Eastern Organ Procurement Foundation (SEOPF) have shown that regional organ procurement (ROP) trays can predict negative crossmatch in highly sensitized patients when the HLA match is of a high grade. In an attempt to offer more well-matched kidneys to highly sensitized patients, SEOPF organized the High Grade Match (HGM) Program. METHODS: This United Network for Organ Sharing (UNOS)-approved allocation variance requires mandatory sharing of all kidneys by participating centers after UNOS mandatory sharing requirements have been met. The HGM levels of sharing are: (1) 0 A,B mismatch (MM); panel-reactive antibody (PRA) > or = 40%; negative ROP crossmatch; (2) 0 B,DR MM with > or = 40% PRA; negative ROP crossmatch; (3) 0 B,DR MM with PRA < 40%. Non-HGM cadaveric transplants at the same participating centers--locally or distally procured--serve as the control group. RESULTS: During the first 18 months of this program, the 23 participating centers shared 124 kidneys of the 1592 that were available. Well-matched kidneys (two mismatches or less) accounted for 91.1% in the HGM group, but only 19% of the controls (P<0.0001). Highly sensitized patients (PRA > or = 40%) represented 13.8% of the HGM group, but only 3.3% of the non-HGM group (P<.0001). With HGM kidneys, there was a shift in recipient demographics. Patients with blood group O, female patients, older patients, and retransplanted patients all accounted for significantly larger percentages of the HGM group compared with the non-HGM control group. The racial composition of the recipients of high-grade matches was, however, no different than that of the control recipients at the same centers. CONCLUSION: The HGM Program resulted in longer ischemia times, but graft survival was not affected. The 1-year actuarial graft survival rate (Kaplan-Meier) for HGM kidneys was not different from the control cadaveric graft survival rate. By sharing kidneys based on improved HLA matches with consideration for high PRA, the HGM Program offered more transplant opportunities to women, blood group O recipients, retransplants, and older patients.

Cold ischemia and outcome in 17,937 cadaveric kidney transplants.

To determine if cold preservation time continues to affect renal transplant outcome, prospectively collected data from 17,937 cadaveric renal transplants performed between 1982 and 1991 were analyzed. Cold preservation intervals of 1-16, 16-32, 32-48, and greater than 48 hr were studied by multi- and univariate methods for two time periods: 1982-1989 (n = 13,800) and 1990-1991 (n = 4137). The functional one-year graft survival for kidneys stored over different intervals was significantly different (P < 0.001) only for the 1982-1989 epoch: one-year allograft survival ranged from 76% (1-16), to 72% (16-32 and 32-48) to 74% (> 48) hr. One-year graft survival ranged from 81 to 83% for the four preservation times in 1990 through 1991 (P = NS). Overall actuarial graft survival was 76% (74% prior to 1990, and 82% after 1990). Factors significantly (P < 0.0001) affecting kidney transplant outcome before and after 1990 were delayed graft function (DGF): n = 4232, 65% one-year graft survival; retransplant status: n = 3029, 67% one-year graft survival; and HLA match at three or more loci: n = 6067, 79% one-year graft survival. While DGF occurred more often with prolonged preservation, kidneys with DGF had similar survival regardless of preservation duration. Before 1990, pretransplant transfusion was associated with better and black recipient race with worse outcome; neither transfusion nor recipient race had any effect after 1990. Patients receiving kidneys preserved for longer periods demonstrate one-year graft survival comparable to kidneys preserved for shorter periods. Prolonged cold ischemic time should no longer be a principal reason for considering organ discard.