Model for end-stage liver disease-based allocation system for liver transplantation in Argentina: does it work outside the United States?

The burden of liver disease in Latin America

Liver disease poses a substantial burden in Latin America. This burden is primarily attributed to a high level of alcohol consumption and the increasing prevalence of risk factors associated with metabolic dysfunction-associated steatotic liver disease (MASLD), such as sedentary lifestyles, easy access to ultra-processed foods, obesity, and type 2 diabetes mellitus. These epidemiological trends are cause for concern, especially considering that there are significant challenges in addressing them due to disparities in access to liver disease screening and care. In this article, we aim to provide an overview of the current situation regarding liver disease in Latin America. We also discuss recent multinational proposals designed to address the growing MASLD burden via its integration into existing non-communicable diseases policies, at both local and global levels. Additionally, we emphasize the urgent need to establish effective public health policies that target both MASLD risk factors and excessive alcohol consumption. Furthermore, we discuss the development of liver transplantation programs, areas for improvement in medical education and research capabilities, and how the fostering of extensive collaboration among all stakeholders is crucial for addressing liver disease in the region.

Liver transplantation in Latin America: reality and challenges

Healthcare systems in Latin America are broadly heterogeneous, but all of them are burdened by a dramatic rise in liver disease. Some challenges that these countries face include an increase in patients requiring a transplant, insufficient rates of organ donation, delayed referral, and inequitable or suboptimal access to liver transplant programs and post-transplant care. This could be improved by expanding the donor pool through the implementation of education programs for citizens and referring physicians, as well as the inclusion of extended criteria donors, living donors and split liver transplantation. Addressing these shortcomings will require national shifts aimed at improving infrastructure, increasing awareness of organ donation, training medical personnel, and providing equitable access to care for all patients.

Liver Diseases in Latin America: Current Status, Unmet Needs, and Opportunities for Improvement

Purpose of review

To assess the current challenges regarding liver diseases, including the burden of disease, access to care, screening, and treatment needs in Latin America.

Recent findings

Latin America is a region with a rich multicultural heritage and important socioeconomic differences. The burden of liver diseases is high and mainly determined by a high level of alcohol intake and the surge of risk factors associated with NAFLD (i.e., sedentary lifestyles, broader access to highly processed foods, obesity, and type 2 diabetes mellitus). Hepatotropic viruses also play a role in the development of chronic liver diseases, although their comparative frequency has been decreasing over the last decades. There are important disparities in access to screening and treatment for liver diseases in Latin America, which are reflected in low access to critical treatments such as direct-acting antiviral agents and drugs to treat hepatocellular carcinoma. Also, important barriers to liver transplantation are present in multiple countries, including a low deceased donors' rate and a lack of availability in several countries (especially in Central America). Our region also has disadvantages in research and education in liver diseases, which limits regional academic development and improvement in quality of care of liver diseases.

Summary

In order to tackle an increasing health burden due to liver diseases, Latin America urgently needs tailored interventions aiming to control the main risk factors for these disorders through the establishment of effective public health policies. Also, development of liver transplantation programs and improvement of medical education and research capabilities as well as extensive collaboration between all stakeholders are keys to address the liver disease agenda in the region.

Liver transplantation for hepatocellular carcinoma: impact of expansion criteria in a multicenter cohort study from a high waitlist mortality region

This study aimed to compare liver transplantation (LT) outcomes and evaluate the potential rise in numbers of LT candidates with hepatocellular carcinoma (HCC) of different allocation policies in a high waitlist mortality region. Three policies were applied in two Latin American cohorts (1085 HCC transplanted patients and 917 listed patients for HCC): (i) Milan criteria with expansion according to UCSF downstaging (UCSF-DS), (ii) the AFP score, and (iii) restrictive policy or Double Eligibility Criteria (DEC; within Milan + AFP score ≤2). Increase in HCC patient numbers was evaluated in an Argentinian prospective validation set (INCUCAI; NCT03775863). Expansion criteria in policy A showed that UCSF-DS [28.4% (CI 12.8-56.2)] or "all-comers" [32.9% (CI 11.9-71.3)] had higher 5-year recurrence rates compared to Milan, with 10.9% increase in HCC patients for LT. The policy B showed lower recurrence rates for AFP scores ≤2 points, even expanding beyond Milan criteria, with a 3.3% increase. Patients within DEC had lower 5-year recurrence rates compared with those beyond DEC [13.3% (CI 10.1-17.3) vs 24.2% (CI 17.4-33.1; P = 0.0006], without significant HCC expansion. In conclusion, although the application of a stricter policy may optimize the selection process, this restrictive policy may lead to ethical concerns in organ allocation (NCT03775863).

Current status of liver transplantation in Latin America

The lack of adequate financial coverage, education, and the organization has been the main limiting factor for the development of transplantation in Latin America. As occurred worldwide, the number of patients on liver waiting lists in Latin America grows disproportionately compared to the number of liver transplantations (LTs) performed. Although many law modifications have been made in the last year, most countries lack social awareness about the importance of donation and the irreversibility of brain death. The mechanisms and norms for organ procurement and infrastructure development, capable of supporting this high demand, are still in slow progress in most countries. Access to LT in the region is very heterogeneous. While some countries have no active LT programs so far, others are an international model of a public transplantation system (Brazil) or a national information system (Argentina). While some countries have only a few LT centers, others have too many LT centers performing an inadequate low number of LTs. Disparity to access transplantation remains the major challenge in the region. Cultural and educational efforts have to be accompanied by transparent public policies that will likely increase organ donation and activity in transplantation. The purpose of this article is to review the trends and current activity in LT within Latin America, based on prior publications and the information available in each country of the region.

Prioritization for liver transplantation using the MELD score in Chile: Inequities generated by MELD exceptions.: A collaboration between the Chilean Liver Transplant Programs, the Public Health Institute and the National Transplant Coordinator

INTRODUCTION AND AIM

The MELD score has been established as an efficient and rigorous prioritization system for liver transplant (LT). Our study aimed to evaluate the effectiveness of the MELD score as a system for prioritization for LT, in terms of decreasing the dropout rate in the waiting list and maintaining an adequate survival post-LT in Chile.

MATERIALS AND METHODS

We analyzed the Chilean Public Health Institute liver transplant registry of candidates listed from October 15th 2011 to December 31st 2014. We included adult candidates (>15 years old) listed for elective cadaveric LT with a MELD score of 15 or higher. Statistical analysis included survival curves (Kaplan-Meier), log-rank statistics and multivariate logistic regression.

RESULTS

420 candidates were analyzed. Mean age was 53.6±11.8 years, and 244 were men (58%). Causes of LT included: Liver cirrhosis without exceptions (HC) 177 (66.4%); hepatocellular carcinoma (HCC) 111 (26.4%); cirrhosis with non-HCC exceptions 102 (24.3%) and non-cirrhotic candidates 30 (7.2%). LT rate was 43.2%. The dropout rate was 37.6% at 1-year. Even though the LT rate was higher, the annual dropout rate was significantly higher in cirrhotic candidates (without exceptions) compared with cirrhotics with HCC, and non-HCC exceptions plus non-cirrhotic candidates (47.9%; 37.2% and 24.2%, respectively, with p=0.004). Post-LT survival was 84% per year, with no significant differences between the three groups (p=0.95).

CONCLUSION

Prioritization for LT using the MELD score system has not decreased the dropout rate in Chile (persistent low donor's rate). Exceptions generate inequities in dropout rate, disadvantaging patients without exceptions.

Hepatocellular carcinoma in Latin America: Diagnosis and treatment challenges

Latin America, a region with a population greater than 600000000 individuals, is well known due to its wide geographic, socio-cultural and economic heterogeneity. Access to health care remains as the main barrier that challenges routine screening, early diagnosis and proper treatment of hepatocellular carcinoma (HCC). Therefore, identification of population at risk, implementation of surveillance programs and access to curative treatments has been poorly obtained in the region. Different retrospective cohort studies from the region have shown flaws in the implementation process of routine surveillance and early HCC diagnosis. Furthermore, adherence to clinical practice guidelines recommendations assessed in two studies from Brazil and Argentina demonstrated that there is also room for improvement in this field, similarly than the one observed in Europe and the United States. In summary, Latin America shares difficulties in HCC decision-making processes similar to those from developed countries. However, a transversal limitation in the region is the poor access to health care with the consequent limitation to standard treatments for overall population. Specifically, universal health care access to the different World Health Organization levels is crucial, including improvement in research, education and continuous medical training in order to expand knowledge and generation of data promoting a continuous improvement in the care of HCC patients.

Characteristics of Liver Transplantation in Argentina: A Multicenter Study

INTRODUCTION

There is a lack of information regarding outcomes after liver transplant in Latin America.

OBJECTIVES

This study sought to describe outcomes after liver transplant in adult patients from Argentina.

METHODS

We performed an ambispective cohort study of adult patients transplanted between June 2010 and October 2012 in 6 centers from Argentina. Only patients who survived after the first 48 hours postransplantation were included. Pretransplantation and posttransplantation data were collected.

RESULTS

A total of 200 patients were included in the study. Median age at time of transplant was 50 (interquartile range [IQR] 26 to 54) years. In total, 173 (86%) patients had cirrhosis, and the most frequent etiology in these patients was hepatitis C (32%). A total of 35 (17%) patients were transplanted with hepatocellular carcinoma. In patients with cirrhosis, the median Model for End-Stage Liver Disease (MELD) score at time of liver transplant was 25 (IQR 19 to 30). Median time on the waiting list for elective patients was 101 (IQR 27 to 295) days, and 3 (IQR 2 to 4) days for urgent patients. Almost 40% of the patients were readmitted during the first 6 months after liver transplant. Acute rejection occurred in 27% of the patients. Biliary and vascular complications were reported in 39 (19%) and 19 (9%) patients, respectively. Renal failure, diabetes, and dyslipidemia were present in 40 (26%), 87 (57%), and 77 (50%) at 2 years, respectively.

CONCLUSIONS

We believe the information contained in this article might be of value for reviewing current practices and developing local policies.

Liver transplantation: Fifty years of experience

Since 1963, when the first human liver transplantation (LT) was performed by Thomas Starzl, the world has witnessed 50 years of development in surgical techniques, immunosuppression, organ allocation, donor selection, and the indications and contraindications for LT. This has led to the mainstream, well-established procedure that has saved innumerable lives worldwide. Today, there are hundreds of liver transplant centres in over 80 countries. This review aims to describe the main aspects of LT regarding the progressive changes that have occurred over the years. We herein review historical aspects since the first experimental studies and the first attempts at human transplantation. We also provide an overview of immunosuppressive agents and their potential side effects, the evolution of the indications and contraindications of LT, the evolution of survival according to different time periods, and the evolution of methods of organ allocation.

Liver Transplantation without Perioperative Transfusions Single-Center Experience Showing Better Early Outcome and Shorter Hospital Stay

Background. Significant amounts of red blood cells (RBCs) transfusions are associated with poor outcome after liver transplantation (LT). We report our series of LT without perioperative RBC (P-RBC) transfusions to evaluate its influence on early and long-term outcomes following LT. Methods. A consecutive series of LT between 2006 and 2011 was analyzed. P-RBC transfusion was defined as one or more RBC units administrated during or ≤48 hours after LT. We divided the cohort in “No-Transfusion” and “Yes-Transfusion.” Preoperative status, graft quality, and intra- and postoperative variables were compared to assess P-RBC transfusion risk factors and postoperative outcome. Results. LT was performed in 127 patients (“No-Transfusion” = 39 versus “Yes-Transfusion” = 88). While median MELD was significantly higher in Yes-Transfusion (11 versus 21; P = 0.0001) group, platelet count, prothrombin time, and hemoglobin were significantly lower. On multivariate analysis, the unique independent risk factor associated with P-RBC transfusions was preoperative hemoglobin (P < 0.001). Incidence of postoperative bacterial infections (10 versus 27%; P = 0.03), median ICU (2 versus 3 days; P = 0.03), and hospital stay (7.5 versus 9 days; P = 0.01) were negatively influenced by P-RBC transfusions. However, 30-day mortality (10 versus 15%) and one- (86 versus 70%) and 3-year (77 versus 66%) survival were equivalent in both groups. Conclusions. Recipient MELD score was not a predictive factor for P-RBC transfusion. Patients requiring P-RBC transfusions had worse postoperative outcome. Therefore, maximum efforts must be focused on improving hemoglobin levels during waiting list time to prevent using P-RBC in LT recipients.

Patients on liver transplantation waiting list with Model for End-Stage Liver Disease score ≥ 30: experience in the Organizzazione Centro Sud Trapianti macro area

INTRODUCTION

From 2011 a program was developed for liver transplant recipients with Model for End-Stage Liver Disease (MELD) score ≥30. We examined its effectiveness and impact on the other subjects on the waiting list.

MATERIALS AND METHODS

We analyzed requests received between January 2011 and May 2012 for the primary pathology, the outcome, the average waiting time, and the origin of the organ. We examined the ordinary waiting list for mortality rates and numbers of transplantations over this period (group A) versus a comparable preceding period (group B).

RESULTS

There were 38 requests for 33 patients. Their primary pathologies were cirrhosis associated with viral infection (n = 15), delayed graft failure (DGF; n = 5), biliary cirrhosis (n = 4), hepatocellular carcinoma (HCC; n = 3 including 2 with cirrhosis), cryptogenic cirrhosis (n = 3), postalcoholic cirrhosis (n = 2), metabolic disease (n = 2), and iatrogenic disease (n = 1). Of the requests, 25 were successfully dealt with, whereas 5 requests were temporarily suspended and 2 were permanently suspended because of better or worse patient conditions. There were 6 deceased patients. Transplanted organs came from the inter-regional area in 64% of cases. The average waiting time was 5.9 days. Within group A were a 311 transplantations among 723 waiting list patients on with a 13.7% mortality rate. Within group B were 305 transplantations among 871 wait-listed patients with a 14% mortality rate.

DISCUSSION

The liver transplantation program for recipients with MELD scores ≥ 30 allowed recipients in critical condition to receive grafts without altering substantially the opportunities for recipients on the elective waiting list.

Improved waiting-list outcomes in Argentina after the adoption of a model for end-stage liver disease-based liver allocation policy

In July 2005, Argentina became the first country after the United States to introduce the Model for End-Stage Liver Disease (MELD) for organ allocation. In this study, we investigated waiting-list (WL) outcomes (n = 3272) and post-liver transplantation (LT) survival in 2 consecutive periods of 5 years before and after the implementation of a MELD-based allocation policy. Data were obtained from the database of the national institute for organ allocation in Argentina. After the adoption of the MELD system, there were significant reductions in WL mortality [28.5% versus 21.9%, P < 0.001, hazard ratio (HR) = 1.57, 95% confidence interval (CI) = 1.37-1.81] and total dropout rates (38.6% versus 29.1%, P < 0.001, HR = 1.31, 95% CI = 1.16-1.48) despite significantly less LT accessibility (57.4% versus 50.7%, P < 0.001, HR = 1.53, 95% CI = 1.39-1.68). The annual number of deaths per 1000 patient-years at risk decreased from 273 in 2005 to 173 in 2010, and the number of LT procedures per 1000 patient-years at risk decreased from 564 to 422. MELD and Model for End-Stage Liver Disease-Sodium scores were excellent predictors of 3-month WL mortality with c statistics of 0.828 and 0.857, respectively (P < 0.001). No difference was observed in 1-year posttransplant survival between the 2 periods (81.1% versus 81.3%). Although patients with a MELD score > 30 had lower posttransplant survival, the global accuracy of the score for predicting outcomes was poor, as indicated by a c statistic of only 0.523. Patients with granted MELD exceptions (158 for hepatocellular carcinoma and 52 for other reasons) had significantly higher access to LT (80.4%) in comparison with nonexception patients with equivalent listing priority (MELD score = 18-25; 54.6%, P < 0.001, HR = 0.49, 95% CI = 0.40-0.61). In conclusion, the adoption of the MELD model in Argentina has resulted in improved liver organ allocation without compromising posttransplant survival.

Liver transplantation using Chagas-infected donors in uninfected recipients: a single-center experience without prophylactic therapy

Organ shortage is the first cause of death on liver transplant waiting lists. As a consequence, we recently decided to expand liver acceptance to those organs that could potentially transmit infectious diseases to their recipients. On January 2010, we initiated a prospective protocol using livers from Chagas-infected donors for transplanting uninfected recipients without using prophylactic therapy. During a 13-month period, 9 of 37 (24%) liver transplants were performed within this protocol. After transplant, each recipient was sequentially and strictly monitored for infection transmission using the Strout method and promptly treated with benznidazole if this occurs. During follow-up, two patients died without Chagas infection and only two (donor-derived T. cruzi transmission rate: 2/9; 22%) patients developed donor-derived Chagas transmission without clinical symptoms. The median follow-up time of the seven live patients was 15 months (range: 13-20). At present, all are symptoms-free with excellent allograft function and without evidence of Chagas disease. In conclusion, we consider that Chagas-infected donors are a promising source of liver grafts that could reduce the growing mortality on liver waiting lists in America. Relevant data from larger prospective studies are required to confirm these preliminary excellent results.

Is it safe to use a liver graft from a Chagas disease-seropositive donor in a human immunodeficiency virus-positive recipient? A case report addressing a novel challenge in liver transplantation

This is the first report presenting a human immunodeficiency virus (HIV)-positive patient with fulminant hepatic failure receiving a liver graft from a Chagas disease-seropositive deceased donor. We describe the history of a 38-year-old HIV-positive female patient who developed fulminant hepatic failure of an autoimmune etiology with rapid deterioration of her clinical status and secondary multiorgan failure and, therefore, needed emergency liver transplantation (LT) as a lifesaving procedure. Because of the scarcity of organs and the high mortality rate for emergency status patients on the LT waiting list, we decided to accept a Chagas disease-seropositive deceased donor liver graft for this immunocompromised Chagas disease-seronegative patient. The recipient had a rapid postoperative recovery and was discharged on postoperative day 9 without prophylactic treatment for Chagas disease. Fifteen months after LT, she was still alive and had never experienced seroconversion on periodic screening tests for Chagas detection. Although there is an inherent risk of acute Chagas disease developing in seronegative recipients, our report suggests that these infected organs can be safely used as a lifesaving strategy for HIV patients with a high need for LT.

Trends in liver transplantation 2011

This review will highlight some of the important recent trends in liver transplantation. When possible, we will compare and contrast these trends across various regions of the world, in an effort to improve global consensus and better recognition of emerging data.