Hyponatremia and mortality among patients on the liver-transplant waiting list

BACKGROUND

Under the current liver-transplantation policy, donor organs are offered to patients with the highest risk of death.

METHODS

Using data derived from all adult candidates for primary liver transplantation who were registered with the Organ Procurement and Transplantation Network in 2005 and 2006, we developed and validated a multivariable survival model to predict mortality at 90 days after registration. The predictor variable was the Model for End-Stage Liver Disease (MELD) score with and without the addition of the serum sodium concentration. The MELD score (on a scale of 6 to 40, with higher values indicating more severe disease) is calculated on the basis of the serum bilirubin and creatinine concentrations and the international normalized ratio for the prothrombin time.

RESULTS

In 2005, there were 6769 registrants, including 1781 who underwent liver transplantation and 422 who died within 90 days after registration on the waiting list. Both the MELD score and the serum sodium concentration were significantly associated with mortality (hazard ratio for death, 1.21 per MELD point and 1.05 per 1-unit decrease in the serum sodium concentration for values between 125 and 140 mmol per liter; P<0.001 for both variables). Furthermore, a significant interaction was found between the MELD score and the serum sodium concentration, indicating that the effect of the serum sodium concentration was greater in patients with a low MELD score. When applied to the data from 2006, when 477 patients died within 3 months after registration on the waiting list, the combination of the MELD score and the serum sodium concentration was considerably higher than the MELD score alone in 32 patients who died (7%). Thus, assignment of priority according to the MELD score combined with the serum sodium concentration might have resulted in transplantation and prevented death.

CONCLUSIONS

This population-wide study shows that the MELD score and the serum sodium concentration are important predictors of survival among candidates for liver transplantation.

Analysis of 462 transplantations from unrelated donors facilitated by the National Marrow Donor Program

BACKGROUND AND METHODS

Allogeneic bone marrow transplantation is curative in a substantial number of patients with hematologic cancers, marrow-failure disorders, immunodeficiency syndromes, and certain metabolic diseases. Unfortunately, only 25 to 30 percent of potential recipients have HLA-identical siblings who can act as donors. In 1986 the National Marrow Donor Program was created in the United States to facilitate the finding and procurement of suitable marrow from unrelated donors for patients lacking related donors.

RESULTS

During the first four years of the program, 462 patients with acquired and congenital lymphohematopoietic disorders or metabolic diseases received marrow transplants from unrelated donors. The probability of engraftment by 100 days after transplantation was 94 percent, although 8 percent of patients later had secondary graft failure. The probability of grade II, III, or IV acute graft-versus-host disease was 64 percent, and the probability of chronic graft-versus-host disease at one year was 55 percent. The rate of disease-free survival at two years among patients with leukemia and good prognostic factors was 40 percent and among patients at higher risk, 19 percent. Twenty-nine percent of the patients with aplastic anemia were alive at two years, and the rate of two-year disease-free survival among patients with myelodysplasia was 18 percent. For patients with congenital immunologic or nonimmunologic disorders, the probability of survival was 52 percent.

CONCLUSIONS

The National Marrow Donor Program has benefited a substantial number of patients in need of marrow transplants from closely HLA-matched unrelated donors and has facilitated the recruitment of unrelated donors into the donor pool and the access to suitable marrow.

Waiting time on dialysis as the strongest modifiable risk factor for renal transplant outcomes: a paired donor kidney analysis

BACKGROUND

Waiting time on dialysis has been shown to be associated with worse outcomes after living and cadaveric transplantation. To validate and quantify end-stage renal disease (ESRD) time as an independent risk factor for kidney transplantation, we compared the outcome of paired donor kidneys, destined to patients who had ESRD more than 2 years compared to patients who had ESRD less than 6 months.

METHODS

We analyzed data available from the U.S. Renal Data System database between 1988 and 1998 by Kaplan-Meier estimates and Cox proportional hazards models to quantify the effect of ESRD time on paired cadaveric kidneys and on all cadaveric kidneys compared to living-donated kidneys.

RESULTS

Five- and 10-year unadjusted graft survival rates were significantly worse in paired kidney recipients who had undergone more than 24 months of dialysis (58% and 29%, respectively) compared to paired kidney recipients who had undergone less than 6 months of dialysis (78% and 63%, respectively; P<0.001 each). Ten-year overall adjusted graft survival for cadaveric transplants was 69% for preemptive transplants versus 39% for transplants after 24 months on dialysis. For living transplants, 10-year overall adjusted graft survival was 75% for preemptive transplants versus 49% for transplants after 24 month on dialysis.

CONCLUSIONS

ESRD time is arguably the strongest independent modifiable risk factor for renal transplant outcomes. Part of the advantage of living-donor versus cadaveric-donor transplantation may be explained by waiting time. This effect is dominant enough that a cadaveric renal transplant recipient with an ESRD time less than 6 months has the equivalent graft survival of living donor transplant recipients who wait on dialysis for more than 2 years.

The new liver allocation system: moving toward evidence-based transplantation policy

In 1999, the Institute of Medicine suggested that instituting a continuous disease severity score that de-emphasizes waiting time could improve the allocation of cadaveric livers for transplantation. This report describes the development and initial implementation of this new plan. The goal was to develop a continuous disease severity scale that uses objective, readily available variables to predict mortality risk in patients with end-stage liver disease and reduce the emphasis on waiting time. Mechanisms were also developed for inclusion of good transplant candidates who do not have high risk of death but for whom transplantation may be urgent. The Model for End-Stage Liver Disease (MELD) and Pediatric End-Stage Liver Disease (PELD) scores were selected as the basis for the new allocation policy because of their high degree of accuracy for predicting death in patients having a variety of liver disease etiologies and across a broad spectrum of liver disease severity. Except for the most urgent patients, all patients will be ranked continuously under the new policy by their MELD/PELD score. Waiting time is used only to prioritize patients with identical MELD/PELD scores. Patients who are not well served by the MELD/PELD scores can be prioritized through a regionalized peer review system. This new liver allocation plan is based on more objective, verifiable measures of disease severity with minimal emphasis on waiting time. Application of such risk models provides an evidenced-based approach on which to base further refinements and improve the model.

Factors influencing families' consent for donation of solid organs for transplantation

CONTEXT

Transplantation has become the therapy of choice for patients with organ failure. However, the low rate of consent by families of donor-eligible patients is a major limiting factor in the success of organ transplantation.

OBJECTIVE

To explore factors associated with the decision to donate among families of potential solid organ donors.

DESIGN AND SETTING

Data collection via chart reviews, telephone interviews with health care practitioners (HCPs) or organ procurement organization (OPO) staff, and face-to-face interviews with family for all donor-eligible deaths at 9 trauma hospitals in southwestern Pennsylvania and northeastern Ohio from 1994 to 1999.

PARTICIPANTS

Family members, HCPs, and OPO staff involved in the donation decision for 420 donor-eligible patients.

MAIN OUTCOME MEASURE

Factors associated with family decision to donate or not donate organs for transplantation.

RESULTS

A total of 238 of the 420 cases led to organ donation; 182 did not. Univariate analysis revealed numerous factors associated with the donation decision. Multivariable analysis of associated variables revealed that family and patient sociodemographics (ethnicity, patient's age and cause of death) and prior knowledge of the patients' wishes were significantly associated with willingness to donate (adjusted odds ratio [OR], 7.68; 95% confidence interval [CI], 6.55-9.01). Families who discussed more topics and had more conversations about organ donation were more likely to donate (adjusted OR, 5.22; 95% CI, 4.32-6.30), as were families with more contact with OPO staff (adjusted OR, 3.08; 95% CI, 2.63-3.60) and those who experienced an optimal request pattern (adjusted OR, 2.96; 95% CI, 2.58-3.40). Socioemotional and communication variables acted as intervening variables.

CONCLUSIONS

Public education is needed to modify attitudes about organ donation prior to a donation opportunity. Specific steps can be taken by HCPs and OPO staff to maximize the opportunity to persuade families to donate their relatives' organs.

Evolution of liver transplantation in Europe: report of the European Liver Transplant Registry

The European Liver Transplant Registry (ELTR) currently allows for the analysis of 44,286 liver transplantations (LTs) performed on 39,196 patients in a 13-year period. After an exponential increase, the number of LTs is plateauing due to a lack of organs. To cope with this, alternatives to cadaveric LT, such as split LT, domino LT, or living-related LT (LRLT) are being used increasingly. They now account for 11% of all procedures. One of the most important findings in the evolution of LT is the considerable improvement of results along time with, for the mean time, a one-year survival of 83%, all indications confounded. The improvement is particularly significant for cancers. This improvement is mainly represented by hepatocellular carcinoma, with a gain of 17% for 5-year survival rate from 1990 to 2000. Increasingly, older donors are used to augment the donor pool and older recipients are transplanted due to improved results and a better selection of patients. More than two thirds of deaths and three quarters of retransplantations occurred within the first year of transplantation. Retransplantation is associated with much less optimal results than first LT. One of the prominent features of recent years is the development of LRLT. LRLT is now performed by almost half of the European centers. As with split LT or domino LT, LRLT aims to provide more patients to be transplanted. Special attention is paid to reducing the risk for the donor, which is now estimated to be 0.5% mortality and 21% postoperative morbidity.

Residual insulin production and pancreatic ß-cell turnover after 50 years of diabetes: Joslin Medalist Study

OBJECTIVE

To evaluate the extent of pancreatic β-cell function in a large number of insulin-dependent diabetic patients with a disease duration of 50 years or longer (Medalists).

RESEARCH DESIGN AND METHODS

Characterization of clinical and biochemical parameters and β-cell function of 411 Medalists with correlation with postmortem morphologic findings of 9 Medalists.

RESULTS

The Medalist cohort, with a mean ± SD disease duration and age of 56.2 ± 5.8 and 67.2 ± 7.5 years, respectively, has a clinical phenotype similar to type 1 diabetes (type 1 diabetes): mean ± SD onset at 11.0 ± 6.4 years, BMI at 26.0 ± 5.1 kg/m(2), insulin dose of 0.46 ± 0.2 u/kg, ∼94% positive for DR3 and/or DR4, and 29.5% positive for either IA2 or glutamic acid decarboxylase (GAD) autoantibodies. Random serum C-peptide levels showed that more than 67.4% of the participants had levels in the minimal (0.03-0.2 nmol/l) or sustained range (≥ 0.2 nmol/l). Parameters associated with higher random C-peptide were lower hemoglobin A1C, older age of onset, higher frequency of HLA DR3 genotype, and responsiveness to a mixed-meal tolerance test (MMTT). Over half of the Medalists with fasting C-peptide > 0.17 nmol/l responded in MMTT by a twofold or greater rise over the course of the test compared to fasting. Postmortem examination of pancreases from nine Medalists showed that all had insulin+ β-cells with some positive for TUNEL staining, indicating apoptosis.

CONCLUSIONS

Demonstration of persistence and function of insulin-producing pancreatic cells suggests the possibility of a steady state of turnover in which stimuli to enhance endogenous β cells could be a viable therapeutic approach in a significant number of patients with type 1 diabetes, even for those with chronic duration.

Results of the first year of the new liver allocation plan

Liver allocation policy in the U.S. was recently changed to a continuous disease severity scale with minimal weight given to time waiting in an effort to better prioritize deceased donor liver transplant candidates. We compared rates of waiting list registrations, removals, transplants, and deaths during the year prior to implementation of the new liver allocation policy (2/27/01-2/26/02, Era 1) with the first year's experience (2/27/02-2/26/03, Era 2) under this new policy. Rates were adjusted for 1,000 patient years on the waiting list and compared using z-tests. A 1-sided test was used to compare death rates; 2-sided tests were used to compare transplant rates. Overall and subgroup analyses were performed for demographic, geographic, and medical strata. In Era 2, we observed a 12% reduction in new liver transplant waiting list registrations, with the largest reductions seen in new registrants with low MELD/PELD scores. In Era 2, there was a 3.5% reduction in waiting list death rate (P =.076) and a 10.2% increase in cadaveric transplants (P <.001). The reduction in waiting list mortality and increase in transplantation rates were evenly distributed across all demographic and medical strata, with some variation across geographic variables. Early patient and graft survival after deceased donor liver transplantation remains unchanged. In conclusion, by eliminating the categorical waiting list prioritization system that emphasized time waiting, the new system has been associated with reduced registrations and improved transplantation rates without increased mortality rates for individual groups of waiting candidates or changes in early transplant survival rates.

Patient-specific embryonic stem cells derived from human SCNT blastocysts

Patient-specific, immune-matched human embryonic stem cells (hESCs) are anticipated to be of great biomedical importance for studies of disease and development and to advance clinical deliberations regarding stem cell transplantation. Eleven hESC lines were established by somatic cell nuclear transfer (SCNT) of skin cells from patients with disease or injury into donated oocytes. These lines, nuclear transfer (NT)-hESCs, grown on human feeders from the same NT donor or from genetically unrelated individuals, were established at high rates, regardless of NT donor sex or age. NT-hESCs were pluripotent, chromosomally normal, and matched the NT patient's DNA. The major histocompatibility complex identity of each NT-hESC when compared to the patient's own showed immunological compatibility, which is important for eventual transplantation. With the generation of these NT-hESCs, evaluations of genetic and epigenetic stability can be made. Additional work remains to be done regarding the development of reliable directed differentiation and the elimination of remaining animal components. Before clinical use of these cells can occur, preclinical evidence is required to prove that transplantation of differentiated NT-hESCs can be safe, effective, and tolerated.

Donation after cardiac death: the University of Wisconsin experience with liver transplantation

OBJECTIVE

To determine whether the outcomes of liver transplantation (LTx) from donation after cardiac death (DCD) donors are equivalent to those from donation after brain death (DBD) donors.

SUMMARY BACKGROUND DATA

Because of the significant donor organ shortage, more transplant centers are using livers recovered from DCD donors. However, long-term, single-center outcomes of liver transplantation from DCD donors are limited.

METHODS

From January 1, 1993, to July 31, 2002, 553 liver transplants were performed from DBD donors and 36 were performed from DCD donors. Differences in event rates between the groups were compared with Kaplan-Meier estimates and the log-rank test. Differences in proportion and differences of means between the groups were compared with Fisher exact test and the Wilcoxon rank sum test, respectively.

RESULTS

Mean warm ischemic time at recovery in the DCD group was 17.8 +/- 10.6 minutes. The overall rate of biliary strictures was greater in the DCD group at 1 year (33% versus 10%) and 3 years (37% versus 12%; P = 0.0001). The incidence of hepatic artery thrombosis, portal vein stenosis/thrombosis, ischemic-type biliary stricture (ITBS), and primary nonfunction were similar between groups. However, the incidence of both hepatic artery stenosis (16.6% versus 5.4%; P = 0.001) and hepatic abscess and biloma formation (16.7% versus 8.3%; P = 0.04) were greater in the DCD group. Trends toward worse patient and graft survival and increased incidence of ITBS were seen in DCD donors greater than 40 years compared with DCD donors less than 40 years. Overall patient survival at 1 year (DCD, 80%; versus DBD, 91%) and 3 years (DCD, 68%; versus DBD, 84%) was significantly less in the DCD group (P = 0.002). Similarly, graft survival at 1 year (DCD, 67%; versus DBD, 86%) and 3 years (DCD, 56%; versus DBD, 80%) were significantly less in the DCD group (P = 0.0001).

CONCLUSIONS

Despite similar rates of primary nonfunction, LTx after controlled DCD resulted in worse patient and graft survival compared with LTx after DBD and increased incidence of biliary complications and hepatic artery stenosis. However, overall results of LTx after controlled DCD are encouraging; and with careful donor and recipient selection, LTx after DCD may successfully increase the donor liver pool.

Survival following liver transplantation from non-heart-beating donors

OBJECTIVE

To determine whether patient and graft survival following transplantation with non-heart-beating donor (NHBD) hepatic allografts is equivalent to heart-beating-donor (HBD) allografts.

SUMMARY BACKGROUND DATA

With the growing disparity between the number of patients awaiting liver transplantation and a limited supply of cadaveric organs, there is renewed interest in the use of hepatic allografts from NHBDs. Limited outcome data addressing this issue exist.

METHODS

Retrospective evaluation of graft and patient survival among adult recipients of NHBD hepatic allografts compared with recipients of HBD livers between 1993 and 2001 using the United Network of Organ Sharing database.

RESULTS

NHBD (N = 144) graft survival was significantly shorter than HBD grafts (N = 26856). One- and 3-year graft survival was 70.2% and 63.3% for NHBD recipients versus 80.4% and 72.1% (P = 0.003 and P = 0.012) for HBD recipients. Recipients of an NHBD graft had a greater incidence of primary nonfunction (11.8 vs. 6.4%, P = 0.008) and retransplantation (13.9% vs. 8.3%, P = 0.04) compared with HBD recipients. Prolonged cold ischemic time and recipient life support were predictors of early graft failure among recipients of NHBD livers. Although differences in patient survival following NHBD versus HBD transplant did not meet statistical significance, a strong trend was evident that likely has relevant clinical implications.

CONCLUSIONS

Graft and patient survival is inferior among recipients of NHBD livers. NHBD donors remain an important source of hepatic grafts; however, judicious use is warranted, including minimization of cold ischemia and use in stable recipients.

Disparities in liver transplantation before and after introduction of the MELD score

CONTEXT

In February 2002, the allocation system for liver transplantation became based on the Model for End-Stage Liver Disease (MELD) score. Before MELD, black patients were more likely to die or become too sick to undergo liver transplantation compared with white patients. Little information exists regarding sex and access to liver transplantation.

OBJECTIVE

To determine the association between race, sex, and liver transplantation following introduction of the MELD system.

DESIGN, SETTING, AND PATIENTS

A retrospective cohort of black and white patients (> or = 18 years) registered on the United Network for Organ Sharing liver transplantation waiting list between January 1, 1996, and December 31, 2000 (pre-MELD cohort, n = 21 895) and between February 28, 2002, and March 31, 2006 (post-MELD cohort, n = 23 793).

MAIN OUTCOME MEASURES

Association between race, sex, and receipt of a liver transplant. Separate multivariable analyses evaluated cohorts within each period to identify predictors of time to death and the odds of dying or receiving liver transplantation within 3 years of listing. Patients with hepatocellular carcinoma were analyzed separately.

RESULTS

Black patients were younger (mean [SD], 49.2 [10.7] vs 52.4 [9.2] years; P < .001) and sicker (MELD score at listing: median [interquartile range], 16 [12-22] vs 14 [11-19]; P < .001) than white patients on the waiting list for both periods. In the pre-MELD cohort, black patients were more likely to die or become too sick for liver transplantation than white patients (27.0% vs 21.7%) within 3 years of registering on the waiting list (odds ratio [OR], 1.51; 95% confidence interval (CI), 1.15-1.98; P = .003). In the post-MELD cohort, black race was no longer associated with increased likelihood of death or becoming too sick for liver transplantation (26.5% vs 22.0%, respectively; OR, 0.96; 95% CI, 0.74-1.26; P = .76). Black patients were also less likely to receive a liver transplant than white patients within 3 years of registering on the waiting list pre-MELD (61.6% vs 66.9%; OR, 0.75; 95% CI, 0.59-0.97; P = .03), whereas post-MELD, race was no longer significantly associated with receipt of a liver transplant (47.5% vs 45.5%, respectively; OR, 1.04; 95% CI, 0.84-1.28; P = .75). Women were more likely than men to die or become too sick for liver transplantation post-MELD (23.7% vs 21.4%; OR, 1.30; 95% CI, 1.08-1.47; P = .003) vs pre-MELD (22.4% vs 21.9%; OR, 1.08; 95% CI, 0.91-1.26; P = .37). Similarly, women were less likely than men to receive a liver transplant within 3 years both pre-MELD (64.8% vs 67.6%; OR, 0.80; 95% CI, 0.70-0.92; P = .002) and post-MELD (39.9% vs 48.7%; OR, 0.70; 95% CI, 0.62-0.79; P < .001).

CONCLUSION

Following introduction of the MELD score to the liver transplantation allocation system, race was no longer associated with receipt of a liver transplant or death on the waiting list, but disparities based on sex remain.

Allogeneic compared with autologous stem cell transplantation in the treatment of patients younger than 46 years with acute myeloid leukemia (AML) in first complete remission (CR1): an intention-to-treat analysis of the EORTC/GIMEMAAML-10 trial

In the European Organization for Research and Treatment of Cancer Leukemia Group and Gruppo Italiano Malattie Ematologiche dell' Adulto (EORTC-LG/GIMEMA) acute myeloid leukemia (AML)-10 trial, patients in first complete remission (CR1) received a single intensive consolidation (IC) course. Subsequently, those patients younger than 46 years with an HLA-identical sibling donor were assigned to undergo allogeneic (allo) stem cell transplantation (SCT), and patients without such a donor were planned for autologous (auto) SCT. Between November 1993 and December 1999, of 1198 patients aged younger than 46 years, 822 achieved CR. The study group constituted 734 patients who received IC: 293 had a sibling donor and 441 did not. Allo-SCT and auto-SCT were performed in 68.9% and 55.8%, respectively. Cytogenetic determination was successfully performed in 446 patients. Risk groups were good (t(8;21), inv16), intermediate (NN or -Y only), and bad/very bad (all others). Median follow-up was 4 years; 289 patients relapsed, 66 died in CR1, and 293 died. Intention-to-treat analysis revealed that the 4-year disease-free survival (DFS) rate of patients with a donor versus those without a donor was 52.2% versus 42.2%, P =.044; hazard ratio = 0.80, 95% confidence interval (0.64, 0.995), the relapse incidence was 30.4% versus 52.5%, death in CR1 was 17.4% versus 5.3%, and the survival rate was 58.3% versus 50.8% (P =.18). The DFS rates in patients with and without a sibling donor were similar in patients with good/intermediate risk but were 43.4% and 18.4%, respectively, in patients with bad/very bad risk cytogenetics. In younger patients (15-35 years), the difference was more pronounced. The strategy to perform early allo-SCT led to better overall results than auto-SCT, especially for younger patients or those with bad/very bad risk cytogenetics.

Early experience with dual kidney transplantation in adults using expanded donor criteria. Double Kidney Transplant Group (DKG)

Dual transplant of marginal kidneys otherwise not considered for single transplant may give access to an expanded pool of cadaveric organs without exposing recipients to the drawbacks of a limited nephron mass supply. This prospective, case-control study compares adverse events and graft outcome in 24 recipients of two marginal kidneys from donors who were >60 yr old or who had diabetes, hypertension, or non-nephrotic proteinuria (cases), with that of 48 age- and gender-matched control subjects who received single ideal grafts at the same center and were given the same immunosuppressive therapy. Marginal kidneys with no macroscopic abnormalities were selected for the double transplant on the basis of a predefined score of histologic damage. Six-month patient and kidney survival was 100% with both of the procedures. Incidence (20.8% versus 20.8%) and median (range) duration of posttransplant anuria (5 [2 to 12] versus 7 [2 to 13] days) were comparable in cases and control subjects, respectively. Time to normal serum creatinine and mean serum creatinine values at each time visit were comparable as well, but with significantly lower levels in cases compared with control subjects from month 2 to last follow-up (1.56 +/- 0.65 versus 1.74 +/- 0.73 mg/dl, P = 0.04). Diastolic BP values averaged during the entire posttransplant period were significantly lower in cases than in control subjects (83.2 +/- 11.5 versus 85.1 +/- 12.5 mmHg, respectively, P = 0.008). Donor/recipient body weight ratio was the only covariate significantly associated at univariate (P = 0.002) and multivariate (P = 0.001) analysis with last available serum creatinine concentrations. Incidence of acute allograft rejections (20.8% versus 18.8%) and of major surgical complications was comparable in the two groups. No renal artery or vein thrombosis was reported in either group. Dual transplants of marginal kidneys are as safe and tolerated as single transplants, and possibly offer an improved filtration power without exposing the recipient to enhanced risk of delayed renal function recovery, acute allograft rejection, or major surgical complications.

Recommendations Implicit in Policy Defaults

Should people be considered organ donors after their death unless they request not to be, or should they not be considered donors unless they request to be? Because people tend to stay with the default in a variety of domains, policymakers' choice of default has large and often important effects. In the United States, where the organ-donation policy default is “not a donor,” about 5,000 people die every year because there are too few donors. Four experiments examined two domains—being an organ donor and saving for retirement—where default effects occur and have important implications. The results indicate that default effects occur in part because policymakers' attitudes can be revealed through their choice of default, and people perceive the default as indicating the recommended course of action. Policymakers need to be aware of the implicit messages conveyed by their choice of default.

Survival Benefit with Kidney Transplants from HLA-Incompatible Live Donors

BACKGROUND

A report from a high-volume single center indicated a survival benefit of receiving a kidney transplant from an HLA-incompatible live donor as compared with remaining on the waiting list, whether or not a kidney from a deceased donor was received. The generalizability of that finding is unclear.

METHODS

In a 22-center study, we estimated the survival benefit for 1025 recipients of kidney transplants from HLA-incompatible live donors who were matched with controls who remained on the waiting list or received a transplant from a deceased donor (waiting-list-or-transplant control group) and controls who remained on the waiting list but did not receive a transplant (waiting-list-only control group). We analyzed the data with and without patients from the highest-volume center in the study.

RESULTS

Recipients of kidney transplants from incompatible live donors had a higher survival rate than either control group at 1 year (95.0%, vs. 94.0% for the waiting-list-or-transplant control group and 89.6% for the waiting-list-only control group), 3 years (91.7% vs. 83.6% and 72.7%, respectively), 5 years (86.0% vs. 74.4% and 59.2%), and 8 years (76.5% vs. 62.9% and 43.9%) (P<0.001 for all comparisons with the two control groups). The survival benefit was significant at 8 years across all levels of donor-specific antibody: 89.2% for recipients of kidney transplants from incompatible live donors who had a positive Luminex assay for anti-HLA antibody but a negative flow-cytometric cross-match versus 65.0% for the waiting-list-or-transplant control group and 47.1% for the waiting-list-only control group; 76.3% for recipients with a positive flow-cytometric cross-match but a negative cytotoxic cross-match versus 63.3% and 43.0% in the two control groups, respectively; and 71.0% for recipients with a positive cytotoxic cross-match versus 61.5% and 43.7%, respectively. The findings did not change when patients from the highest-volume center were excluded.

CONCLUSIONS

This multicenter study validated single-center evidence that patients who received kidney transplants from HLA-incompatible live donors had a substantial survival benefit as compared with patients who did not undergo transplantation and those who waited for transplants from deceased donors. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases.).

Biliary atresia: current concepts and research directions. Summary of a symposium

Biliary atresia (BA) is the end result of a destructive, inflammatory process that affects intra- and extrahepatic bile ducts, leading to fibrosis and obliteration of the biliary tract with the development of biliary cirrhosis. It is the commonest cause of chronic cholestasis in infants and children, and therefore is the most frequent indication for liver transplantation in this age group. The disease occurs worldwide, affecting an estimated 1 in 8,000 to 12,000 live births. At present, there is no specific therapy for BA; however, sequential surgical therapy begins with creation of a hepatoportoenterostomy (HPE); in those with end-stage liver disease, liver transplantation is indicated. Since most candidates are young children of small size, there is a shortage of size-matched donors for liver transplantation. At present, an increased awareness to ensure early diagnosis and development of methods to prevent progressive fibrosis are needed. These considerations are dependent on detailed studies of the pathogenesis of BA. Recent studies have focused on normal and altered bile duct morphogenesis and the role of various factors (infectious or toxic agents and metabolic insults) in isolation or in combination with a genetic or immunologic susceptibility in the etiology of BA.

Selection and outcome of living donors for adult to adult right lobe transplantation

BACKGROUND

The shortage of cadaveric livers has sparked an interest in adult-to-adult living donor transplantation. Right lobe donor hepatectomy is frequently required to obtain a graft of adequate size for adult recipients. Careful donor selection is necessary to minimize complications and assure a functional graft.

METHODS

A four-step evaluation protocol was used for donor selection and satisfactory results of all tests in each step were required before proceeding to the next. Donors were selected based on a battery of laboratory studies chosen to exclude unrecognized infection, liver disease, metabolic disorders, and conditions representing undue surgical risk. Imaging studies included ultrasonography, angiography, magnetic resonance imaging, and intraoperative cholangiography and ultrasonography. The information obtained from liver biopsy was used to correct the estimated graft mass for the degree of steatosis.

RESULTS

From March 1998 to August 1999, 126 candidates were evaluated for living donation. A total of 35 underwent donor right lobectomy with no significant complications. Forty percent of all donors that came to surgery were genetically unrelated to the recipient. A total of 69% of those evaluated were excluded. ABO incompatibility was the primary reason for exclusion after the first step (71%) and the presence of steatosis yielding an inadequate estimated graft mass after the second step (20%).

CONCLUSIONS

Donor selection limits the application of living donor liver transplantation in the adult population. Unrelated individuals increase the size of the donor pool. Right lobe hepatectomy can be performed safely in healthy adult liver donors. Preoperative liver biopsy is an essential part of the evaluation protocol, particularly when the estimated graft mass is marginal.

Variables in organ donors that affect the recovery of human islets of Langerhans

In an attempt to reduce the variability in the yields of human islets isolations and to identify donor factors that were potentially deleterious, we retrospectively reviewed 153 human islets isolations in our center over a 3-year period. Isolations were performed using controlled collagenase perfusion via the duct, automated dissociation, and Ficoll purification. Factors leading to successful isolations (recovery of >100,000 islet equivalents at a purity >50%) were analyzed retrospectively using univariate and multivariate analysis. Critical factors in the multiorgan cadaveric donors that were identified using univariate analysis included donor age (P<0.01), body mass index (BMI)(P<0.01), cause of death (P<0.01), and prolonged hypotensive episodes (systolic blood pressure <90 mmHg or mean arterial pressure <60 mmHg for > 15 min) requiring high vasopressors (>15 microgram/kg/min dopamine or >5 microgram/kg/min Levophed) (P>0.01). Independent analysis of 19 donor variables using multivariate logistic stepwise regression showed six factors were statistically significant. Odds ratio (OR) showed that donor age (OR 1.1, P<0.01), local procurement team (OR 10.9, P<0.01), and high BMI (OR 1.4, P<0.01) had a positive correlation with islet recovery. In contrast, hyperglycemia (all blood glucose >10 mmol/L) (OR 0.63, P<0.01), frequency and duration of cardiac arrest (OR 0.7, P<0.01), and increased duration of cold storage before islet isolation (OR 0.83, P<0.01) had negative correlation. Using these combinations of factors, the prediction of success was 85% accurate. By donor age, success was 13% for 2.5- to 18-year-old donors (n=23), 37% for 19- to 28-year-old donors (n=30), 65% for 29- to 50-year-old donors (n=70), and 83% for 51- to 65-year-old (n=29) donors. However, when vitro function was assessed by perifusion, the insulin secretory capabilities of islets isolated from the >50-year-old donor group was significantly reduced as compared with the 2.5- to 18-year-old group (P<0.02). Multiple regression analysis using postdigestion and postpurification islet recovery as outcome variables identified BMI, procurement team, pancreas weight, and collagenase digestion time factors tht can affect the recovery of human islets. Locally procured pancreases and donors with elevated minimum blood glucose levels were identified as factors that affect the insulin secretory capabilities of the isolated islets. This review of parameters suggests an improved approach to the prediction of successful islet isolation from human pancreases. Selection of suitable pancreases for processing may improve consistency in human islet isolation and thereby decrease costs.

Outcomes of DCD liver transplantation using organs treated by hypothermic oxygenated perfusion before implantation

BACKGROUND & AIMS

Donation after circulatory death (DCD) liver transplantation is known for potentially worse outcomes because of higher rates of graft non-function or irreversible cholangiopathy. The impact of machine liver perfusion techniques on these complications remains elusive. We aimed to provide data on 5-year outcomes in patients receiving DCD liver transplants, after donor organs had been treated by hypothermic oxygenated perfusion (HOPE).

METHODS

Fifty HOPE-treated DCD liver transplants performed in Zurich between 2012 and 3/2017 were matched with 50 primary donation after brain death (DBD) liver transplants, and with 50 untreated DCD liver transplants in Birmingham. Match factors focussed on short cold ischaemia, comparable recipient age and low recipient laboratory model for end-stage liver disease scores. Primary endpoints were post-transplant complications, and non-tumour-related patient death or graft loss.

RESULTS

Despite extended donor warm ischaemia, HOPE-treated DCD liver transplants achieved similar overall graft survival, compared to standard DBD liver transplants. Particularly, graft loss due to any non-tumour-related causes occurred in 8% (4/50) of cases. In contrast, untreated DCD livers resulted in non-tumour-related graft failure in one-third (16/50) of cases (p = 0.005), despite significantly (p <0.001) shorter functional donor warm ischaemia. Five-year graft survival, censored for tumour death, was 94% for HOPE-treated DCD liver transplants vs. 78% in untreated DCD liver transplants (p = 0.024).

CONCLUSIONS

The 5-year outcomes of HOPE-treated DCD liver transplants were similar to those of DBD primary transplants and superior to those of untreated DCD liver transplants, despite much higher risk. These results suggest that a simple end-ischaemic perfusion approach is very effective and may open the field for safe utilisation of extended DCD liver grafts.

LAY SUMMARY

Machine perfusion techniques are currently being introduced into the clinic, with the aim of optimising injured grafts prior to implantation. While short-term effects of machine liver perfusion have been frequently reported in terms of hepatocellular enzyme release and early graft function, the long-term benefit on irreversible graft loss has been unclear. Herein, we report on 5-year graft survival in donation after cardiac death livers, treated either by conventional cold storage, or by 1-2 h of hypothermic oxygenated perfusion (HOPE) after cold storage. Graft loss was significantly less in HOPE-treated livers, despite longer donor warm ischaemia times. Therefore, HOPE after cold storage appears to be a simple and effective method to treat high-risk livers before implantation.

Assessing priorities for allocation of donor liver grafts: survey of public and clinicians

OBJECTIVES

To compare the priorities of the general public, family doctors, and gastroenterologists in allocating donor livers to potential recipients of liver allograft.

DESIGN

Representative quota sampling of 1000 members of the general public and 200 family doctors, and a postal questionnaire of 100 gastroenterologists.

SUBJECTS

Respondents were given eight hypothetical case histories (based on real patients) and asked to select recipients for four donor livers. Cases were selected to identify controversial areas such as extremes of age, misuse of alcohol, and intravenous drugs. Respondents were also asked to select the least deserving case and which of seven possible factors (time on waiting list, outcome, age, value to society, return to work, previous use of illicit drugs, and involvement of alcohol in the liver damage) should be used to select patients already listed for transplantation. Focus groups were also held to explore further the reasons for the choices given.

RESULTS

There were considerable differences between the three groups in the choice of the recipients, although alcohol use and antisocial behaviour always rated low. For selection of recipients the general public thought that, in decreasing order of importance, age, outcome, and time on the waiting list were the most important factors in selecting recipients; family doctors rated outcome, age, and likely work status after transplantation and the gastroenterologists outcome, work status, and non-involvement of alcohol in the cause of the liver disease as the most important factors.

CONCLUSIONS

The views of the public are at variance with those of clinicians. Further debate is required to ensure an equitable and appropriate distribution of a scarce resource.

Pancreas transplantation

Since the introduction of pancreas transplantation more than 40 years ago, efforts to develop more minimally invasive techniques for endocrine replacement therapy have been in progress, yet this surgical procedure still remains the treatment of choice for diabetic patients with end-stage renal failure. Many improvements have been made in the surgical techniques and immunosuppressive regimens, both of which have contributed to an increasing number of indications for pancreas transplantation. This operation can be justified on the basis that patients replace daily injections of insulin with an improved quality of life but at the expense of a major surgical procedure and lifelong immunosuppression. The various indications, categories, and outcomes of patients having a pancreas transplant are discussed, particularly with reference to the effect on long-term diabetic complications.