Geographic Disparities in Liver Availability: Accidents of Geography, or Consequences of Poor Social Policy?

Recently, a redistricting proposal intended to equalize Model for End-stage Liver Disease score at transplant recommended expanding liver sharing to mitigate geographic variation in liver transplantation. Yet, it is unclear whether variation in liver availability is arbitrary and a disparity requiring rectification or reflects differences in access to care. We evaluate the proposal's claim that organ supply is an "accident of geography" by examining the relationship between local organ supply and the uneven landscape of social determinants and policies that contribute to differential death rates across the United States. We show that higher mortality leading to greater availability of organs may in part result from disproportionate risks incurred at the local level. Disparities in public safety laws, health care infrastructure, and public funding may influence the risk of death and subsequent availability of deceased donors. These risk factors are disproportionately prevalent in regions with high organ supply. Policies calling for organ redistribution from high-supply to low-supply regions may exacerbate existing social and health inequalities by redistributing the single benefit (greater organ availability) of greater exposure to environmental and contextual risks (e.g. violent death, healthcare scarcity). Variation in liver availability may not be an "accident of geography" but rather a byproduct of disadvantage.

A genomic case study of mixed fibrolamellar hepatocellular carcinoma.

BACKGROUND: Mixed fibrolamellar hepatocellular carcinoma (mFL-HCC) is a rare liver tumor defined by the presence of both pure FL-HCC and conventional HCC components, represents up to 25% of cases of FL-HCC, and has been associated with worse prognosis. Recent genomic characterization of pure FL-HCC identified a highly recurrent transcript fusion (DNAJB1:PRKACA) not found in conventional HCC. PATIENTS AND METHODS: We performed exome and transcriptome sequencing of a case of mFL-HCC. A novel BAC-capture approach was developed to identify a 400 kb deletion as the underlying genomic mechanism for a DNAJB1:PRKACA fusion in this case. A sensitive Nanostring Elements assay was used to screen for this transcript fusion in a second case of mFL-HCC, 112 additional HCC samples and 44 adjacent non-tumor liver samples. RESULTS: We report the first comprehensive genomic analysis of a case of mFL-HCC. No common HCC-associated mutations were identified. The very low mutation rate of this case, large number of mostly single-copy, long-range copy number variants, and high expression of ERBB2 were more consistent with previous reports of pure FL-HCC than conventional HCC. In particular, the DNAJB1:PRKACA fusion transcript specifically associated with pure FL-HCC was detected at very high expression levels. Subsequent analysis revealed the presence of this fusion in all primary and metastatic samples, including those with mixed or conventional HCC pathology. A second case of mFL-HCC confirmed our finding that the fusion was detectable in conventional components. An expanded screen identified a third case of fusion-positive HCC, which upon review, also had both conventional and fibrolamellar features. This screen confirmed the absence of the fusion in all conventional HCC and adjacent non-tumor liver samples. CONCLUSION: These results indicate that mFL-HCC is similar to pure FL-HCC at the genomic level and the DNAJB1:PRKACA fusion can be used as a diagnostic tool for both pure and mFL-HCC.

Liver transplantation in a patient with developmental interruption of the inferior vena cava with azygos substitution.

Infrahepatic interruption of the inferior vena cava (IVC) with azygos or hemiazygos substitution has been reported frequently in children with biliary atresia where this venous abnormality is associated with other venous abnormalities such as preduodenal portal vein or congenital heart disease. It is important to recognize this anomaly pretransplant because the hepatic vein may drain directly into the right atrium rather than into the suprahepatic vena cava. We describe herein the first report of an orthotopic deceased donor liver transplant in an adult patient with an interrupted IVC and azygos continuation. We also review the embryological development of the IVC and the vascular anomalies that can occur.

A consolidated biovigilance system for blood, tissue and organs: one size does not fit all.

Biovigilance systems to assess and analyze risks for disease transmission through the transfer of organs, tissue, cells and blood between people is part of administrative oversight and has impact upon clinical practice and policy. In 2009, a formal recommendation by the Public Health Service requested that Health and Human Services fund and support efforts to consolidate national biovigilance efforts. There are differences in the biovigilance issues involved in organ and tissue donation/transplantation. If disease avoidance is made the dominant principle guiding organ donor testing, an unintended consequence may be an increase in deaths on the waiting list. We propose that overall benefit for the organ transplant recipient, tempered by patient informed awareness of limited organ availability and assessment processes, should be the guiding principle of such a system.

Rational rationing or discrimination: balancing equity and efficiency considerations in kidney allocation.

After 6 years of deliberation, the Organ Procurement and Transplantation Network recently released a concept document proposing changes to the kidney allocation algorithm, sparking a heated debate about priority-setting of scarce health resources and discrimination. Proponents of the proposal argue that it will result in an additional 15,223 life years following transplant annually for recipients, yet the benefit will not be equally distributed and will likely benefit younger patients. Critics argue that the new model will promote age discrimination and may lead to a further decrease in live kidney donation. If true, these concerns could undermine fairness and damage public trust in the organ allocation system. We address these objections and consider their merit, highlighting both benefits and shortcomings of the proposal. We argue that, despite weaknesses of the proposal and the importance of maintaining consistency in patient and provider expectations over time, the proposal represents a needed first step in balancing equity and efficiency.

Patients' willingness to accept expanded criteria donor liver transplantation.

Utilization of livers from expanded criteria donors (ECD) is one strategy to overcome the severe organ shortage. The decision to utilize an ECD liver is complex and fraught with uncertainty for both providers and patients. We assessed patients' willingness to accept ECD liver transplantation (LTx) and acceptable 1-year mortality risk. One hundred eight patients listed for LTx were asked to rate their willingness to accept ECD LTx and the associated 1-year mortality risk they were willing to accept. Also, patients completed the SF-36v2 and sociodemographic and health information was gathered from their medical records. Patients reported significantly higher willingness to accept standard criteria donor (SCD) versus ECD LTx (t = 13.8, p < 0.001), with more than one-third of patients reporting low willingness to accept ECD LTx. Relative to our center's 10% SCD LTx 1-year mortality rate, most patients (71%) were willing to accept moderately or substantially higher 1-year mortality risk for ECD LTx. In multivariable analyses, higher lab MELD score and white race were significant independent predictors of both ECD willingness and ECD increased mortality risk acceptability. Findings highlight the importance of assessing patients' willingness to pursue ECD LTx and the relative mortality risks they are willing to accept.

Intraoperative administration of inhaled carbon monoxide reduces delayed graft function in kidney allografts in Swine.

Ischemia/reperfusion injury and delayed graft function (DGF) following organ transplantation adversely affect graft function and survival. A large animal model has not been characterized. We developed a pig kidney allograft model of DGF and evaluated the cytoprotective effects of inhaled carbon monoxide (CO). We demonstrate that donor warm ischemia time is a critical determinant of DGF as evidenced by a transient (4-6 days) increase in serum creatinine and blood urea nitrogen following transplantation before returning to baseline. CO administered to recipients intraoperatively for 1 h restored kidney function more rapidly versus air-treated controls. CO reduced acute tubular necrosis, apoptosis, tissue factor expression and P-selectin expression and enhanced proliferative repair as measured by phosphorylation of retinol binding protein and histone H3. Gene microarray analyses with confirmatory PCR of biopsy specimens showed that CO blocked proinflammatory gene expression of MCP-1 and heat shock proteins. In vitro in pig renal epithelial cells, CO blocks anoxia-reoxygenation-induced cell death while promoting proliferation. This large animal model of DGF can be utilized for testing therapeutic strategies to reduce or prevent DGF in humans. The efficacy of CO on improving graft function posttransplant validates the model and offers a potentially important therapeutic strategy to improve transplant outcomes.

Understanding disparities in transplantation: do social networks provide the missing clue?

Although the National Organ Transplant Act calls for equity in access to transplantation, scarcity and racial disparities persist. To date, even the most comprehensive models have been unable to adequately explain these racial disparities, leaving policymakers unsure how best to intervene. Previous individual-level analyses, which have implicated risk factors such as race, financial status, cultural beliefs, unemployment, lack of commitment to surgery and lack of continuous access to care, overlook contextual and social network exposures. Social networks present a compelling way to examine cumulative risk clustered across individuals. Social networks have been shown to influence health outcomes and health behaviors through various pathways, including shared social capital, engaging in similar or group risky behaviors, diffusion of information and adopting or propagating social norms. Precursors to chronic kidney disease, including obesity, have been shown to spread through social networks. Social network analysis can reveal shared risks between potential donors and recipients in a given network, clarifying the likelihood of finding an appropriate match through either direct donation or paired exchanges. This paper presents a novel application of social network analysis to transplantation, illustrating implications for disparities and future clinical interventions.

ASTS recommended practice guidelines for controlled donation after cardiac death organ procurement and transplantation.

The American Society of Transplant Surgeons (ASTS) champions efforts to increase organ donation. Controlled donation after cardiac death (DCD) offers the family and the patient with a hopeless prognosis the option to donate when brain death criteria will not be met. Although DCD is increasing, this endeavor is still in the midst of development. DCD protocols, recovery techniques and organ acceptance criteria vary among organ procurement organizations and transplant centers. Growing enthusiasm for DCD has been tempered by the decreased yield of transplantable organs and less favorable posttransplant outcomes compared with donation after brain death. Logistics and ethics relevant to DCD engender discussion and debate among lay and medical communities. Regulatory oversight of the mandate to increase DCD and a recent lawsuit involving professional behavior during an attempted DCD have fueled scrutiny of this activity. Within this setting, the ASTS Council sought best-practice guidelines for controlled DCD organ donation and transplantation. The proposed guidelines are evidence based when possible. They cover many aspects of DCD kidney, liver and pancreas transplantation, including donor characteristics, consent, withdrawal of ventilatory support, operative technique, ischemia times, machine perfusion, recipient considerations and biliary issues. DCD organ transplantation involves unique challenges that these recommendations seek to address.

Framing disparities along the continuum of care from chronic kidney disease to transplantation: barriers and interventions.

Research in renal transplantation continues to document scores of disparities affecting vulnerable populations at various stages along the transplantation process. Given that both biological and environmental determinants contribute significantly to variation, identifying factors underlying an unfairly biased distribution of the disease burden is crucial. Confounded definitions and gaps in understanding causal pathways impede effectiveness of interventions aimed at alleviating disparities. This article offers an operational definition of disparities in the context of a framework aimed at facilitating interventional research. Utilizing an original framework describing the entire continuum of the transplant process from diagnosis of chronic kidney disease through successful transplant, this article explores the case of racial disparities, illustrating key factors predicting and perpetuating disparities. Though gaps in current research leave us unable to identify which stages of the transplant pathway adversely affect most people, by identifying key risk factors across the continuum of care, this article highlights areas suited for targeted interventions and presents recommendations for improvement and future research.

Evaluating living kidney donors: relationship types, psychosocial criteria, and consent processes at US transplant programs.

We conducted a survey of 132 US kidney transplant programs to examine how they evaluate and select potential living kidney donors, focusing on donor-recipient relationships, psychosocial criteria, and consent processes. There is heterogeneity in donor-recipient relationships that are considered acceptable, although most programs (70%) will not consider publicly solicited donors. Most programs (75%) require a psychosocial evaluation for all potential living donors. Most programs agree that knowledge of financial reward (90%), active substance abuse (86%), and active mental health problems (76%) are absolute contraindications to donation. However, there is greater variability in how other psychosocial issues are considered in the selection process. Consent processes are highly variable across programs: donor and recipient consent for the donor evaluation is presumed in 57% and 76% of programs, respectively. The use of 13 different informed consent elements varied from 65% (alternative donation procedures) to 86% (description of evaluation, surgery and recuperative period) of programs. Forty-three percent use a 'cooling off' period. Findings demonstrate high variability in current practice regarding acceptable donor-recipient relationships, psychosocial criteria, and consent processes. Whether greater consensus should be reached on these donor evaluation practices, especially in the context of more expansive use of living donor kidney transplantation, is discussed.

The medical evaluation of living kidney donors: a survey of US transplant centers.

The use of living donors for kidney transplantation in the United States is common, and long-term studies have demonstrated the safety of donation by young, healthy individuals. However, transplant programs have little data to guide them in deciding which donors are unacceptable, and which characteristics are associated with kidney disease or poor psychosocial outcomes after donation. To document current practices in evaluating potential donors, we surveyed all US kidney transplant programs. Compared to a survey 12 years ago, medical criteria for donation are more inclusive in several areas. All responding programs now accept living unrelated donors. Most programs no longer have an upper age limit to be eligible. Programs are now more likely to accept donors with treated hypertension, or a history of kidney stones, provided that certain additional criteria are met. In contrast, medical criteria for donation are more restrictive in other areas, such as younger donor age and low creatinine clearance. Overall, significant variability remains among transplant programs in the criteria used to evaluate donors. These findings highlight the need for more data on long-term outcomes in various types of donors with potential morbidities related to donation.

Primary nonfunction (PNF) in the MELD Era: An SRTR database analysis.

PNF following liver transplantation (LT) is an infrequent but life-threatening complication. Liver allocation under MELD is based upon recipient severity of illness, a known risk factor for the occurrence of PNF. The incidence of PNF since the application of MELD has not previously been reported. The SRTR database was studied since inception of MELD until September 2004 for all adult recipients of deceased donor LT. PNF was defined as graft loss or death within 14 days of LT secondary to PNF or without defined cause. A total of 10545 transplants met inclusion criteria and PNF occurred in 613 (5.81%) of recipients. Univariate analysis demonstrated donor age, serum creatinine >1.5 mg/mL, hypertension and CVA as risk factors for PNF. Recipient factors included life support, mechanical ventilation, use of inotropes, hemodialysis, initial status 1 and use of a shared transplant. In the multivariate model only donor age and recipient serum creatinine, bilirubin, on life support and status 1 at transplant were significant risk factors for PNF. In this analysis of PNF in the MELD era the incidence of PNF does not appear to have increased from prior reports. Risk factors for PNF are related to donor age and severity of recipient illness.