Comparative Study Between Living and Cadaveric Donors in Pediatric Liver Transplantation

Long-term Outcomes of Pediatric Living Versus Deceased Donor Liver Transplantation Recipients: A Systematic Review and Meta-analysis

Living donor liver transplantation (LDLT) emerged in the 1980s as a viable alternative to scarce cadaveric organs for pediatric patients. However, pediatric waitlist mortality remains high. Long-term outcomes of living and deceased donor liver transplantation (DDLT) are inconsistently described in the literature. Our aim was to systematically review the safety and efficacy of LDLT after 1 year of transplantation among pediatric patients with all causes of liver failure. We searched the MEDLINE, Medline-in-Process, MEDLINE Epub Ahead of Print, Embase + Embase Classic (OvidSP), and Cochrane (Wiley) from February 1, 1947 to February 26, 2020, without language restrictions. The primary outcomes were patient and graft survival beyond 1 year following transplantation. A meta-analysis of unadjusted and adjusted odds and hazard ratios was performed using a random-effects model. A total of 24 studies with 3677 patients who underwent LDLT and 9098 patients who underwent DDLT were included for analysis. In patients with chronic or combined chronic liver failure and acute liver failure (ALF), 1-year (odds ratio [OR], 0.68; 95% confidence interval [CI], 0.53-0.88), 3-year (OR, 0.73; 95% CI, 0.61-0.89), 5-year (OR, 0.71; 95% CI, 0.57-0.89), and 10-year (OR, 0.42; 95% CI, 0.18-1.00) patient and 1-year (OR, 0.50; 95% CI, 0.35-0.70), 3-year (OR, 0.55; 95% CI, 0.37-0.83), 5-year (OR, 0.5; 95% CI, 0.32-0.76), and 10-year (OR, 0.26; 95% CI, 0.14-0.49) graft survival were consistently better in LDLT recipients compared with those in DDLT recipients. In patients with ALF, no difference was seen between the 2 groups except for 5-year patient survival (OR, 0.60; 95% CI, 0.38-0.95), which favored LDLT. Sensitivity analysis by era showed improved survival in the most recent cohort of patients, consistent with the well-described learning curve for the LDLT technique. LDLT provides superior patient and graft survival outcomes relative to DDLT in pediatric patients with chronic liver failure and ALF. More resources may be needed to develop infrastructures and health care systems to support living liver donation.

Living Donor Versus Deceased Donor Pediatric Liver Transplantation: A Systematic Review and Meta-analysis

Reduced-size deceased donors and living donor liver transplantation (LDLT) can address the organ shortage for pediatric liver transplant candidates, but concerns regarding technical challenges and the risk of complications using these grafts have been raised. The aim of this study was to compare outcomes for pediatric LDLT and deceased donor liver transplantation (DDLT) via systematic review.

METHODS

A systematic literature search was performed to identify studies reporting outcomes of pediatric (<18 y) LDLT and DDLT published between 2005 and 2019. A meta-analysis was conducted to examine peri- and postoperative outcomes using fixed- and random-effects models.

RESULTS

Overall, 2518 abstracts were screened, and 10 studies met criteria for inclusion. In total, 1622 LDLT and 6326 DDLT pediatric patients from 4 continents were examined. LDLT resulted in superior patient survival when compared with DDLT at 1, 3, and 5 y post-LT (1-y hazard ratio: 0.58, 95% confidence interval [CI] 0.47-0.73, P < 0.0001). Similarly, LDLT resulted in superior graft survival at all time points post-LT when compared with DDLT (1-y hazard ratio: 0.56 [95% CI 0.46-0.68], P < 0.0001]. The OR for vascular complications was 0.73 (95% CI 0.39-1.39) and 1.31 (95% CI 0.92-1.86) for biliary complications in LDLT compared with DDLT, whereas LDLT was associated with lower rates of rejection (OR: 0.66 [95% CI 0.45-0.96], P = 0.03).

CONCLUSIONS

This meta-analysis demonstrates that LDLT may offer many advantages when compared with DDLT in children and suggests that LDLT should continue to be expanded to optimize outcomes for pediatric LT candidates.

Adult-to-adult living donor liver transplantation preoperative survey using MDCT, a single medical center experience in Taiwan

This study evaluated multi-detector computed tomography (MDCT) scans performed on potential living donors for adult-to-adult liver transplantation (LDLT), with the aim of identifying significant findings that could be used to exclude potential transplantation donors. We retrospectively reviewed the medical records of 151 consecutive potential adult donors for LDLT from May 2007 to January 2015. Liver parenchyma steatosis, focal hepatic mass or intraabdominal malignancy, vascular variations, and donor liver volume were evaluated via MDCT. Grounds for excluding potential donors were also recorded and analyzed. Of the 151 potential donors, nine (6.0%) had moderate to severe fatty liver, 37 (24.5%) had hepatic arterial variants, 22 (14.6%) had significant portal venous variants, and more than half were found to have right accessory inferior hepatic vein. No intraabdominal malignancies were found. Eighty-eight potential donors were rejected, with the most common cause being insufficient recipient volume or remnant donor volume (47.7%), moderate to severe parenchymal steatosis (10.2%), and recipient expiration prior to transplantation (8.0%). An additional 16 potential donors were excluded by the surgical team due to the complexity of their portal venous variations. The rate of exclusion by pre-transplant imaging evaluation with MDCT was 33.8%. MDCT can provide accurate quantification of donor liver volume and steatosis severity along with precise demonstration of vascular variants, which are crucial for the preoperative evaluation of LDLT. However, MDCT may be ineffective for evaluating the biliary system without hepatobiliary-excreted contrast agent and has the disadvantage of ionizing radiation.

Peripheral blood biomarkers for the characterization of alloimmune reactivity after pediatric liver transplantation

Individualization of immunosuppressive medications is an important objective in transplantation medicine. Reliable biomarkers to distinguish between patients dependent from intensive immunosuppressive therapy and those where therapy can be minimized among pediatric transplant recipients receiving immunosuppressive medications are still not established. We evaluated the potential of cross-sectional quantification of regulatory T cells, lymphocyte subsets, and cytokine concentrations as biomarkers in 60 pediatric liver transplant recipients with AR, CR, or normal graft function and in 11 non-transplanted patients. Transplant recipients presenting with AR had significantly higher CD8+ T-cell counts, significantly higher concentrations of IL-2, and increased levels of IFN-γ compared with asymptomatic patients or controls. Regulatory T-cell numbers did not differ between children with rejection and children with good graft function. A tendency toward increased concentrations of IL-4 and TGF-β was detected in transplant recipients with good graft function. Cross-sectional parameters of peripheral regulatory T cells in pediatric liver transplant recipients do not seem to be valuable biomarkers for individualizing immunosuppressive therapy prior to the weaning process. Lymphocyte subsets, IL-2, IFN-γ, IL-4, and TGF-β serum concentrations may be helpful to identify children in whom immunosuppression can be reduced or discontinued.

Cytokine concentrations and regulatory T cells in living donor and deceased donor liver transplant recipients

Outcomes of pediatric liver transplantation have constantly improved in the last decade. Living-related liver transplantation does not seem to improve long-term outcomes following liver transplantation, but few studies have evaluated immunological parameters of the alloimmune response after living vs. deceased donor organ transplantation. We analyzed numbers of regulatory T cells, lymphocyte subsets, and serum cytokine concentrations in 12 pediatric recipients of living-related liver transplants and in 28 pediatric recipients of deceased donor organs during their annual follow-ups. Transplant recipients who underwent living donor organ transplantation had significantly higher numbers of regulatory T cells and IL-4 serum concentrations than recipients of deceased donor organs; both of these factors are associated with beneficial outcomes and transplantation tolerance. Living-related liver transplantation may have potentially beneficial immunological aspects, although long-term outcomes do not seem to be better in recipients of living donor organs than in recipients of deceased donor organs. Further studies are needed to compare immunological aspects of the two transplant procedures.

Biliary complications following deceased and living donor liver transplantation: a review

INTRODUCTION

Biliary complications are the most important source of complications after liver transplantation, and an important cause of morbidity and mortality. With the evolution of surgical transplantation techniques, including living donor and split-liver transplants, the complexity of these problems is increasing. Many studies have shown a higher incidence of biliary tract complications in living donor liver transplantation (LDLT) compared with deceased donor liver transplantation (DDLT). This article reviews biliary complications after liver transplantation and correlations with LDLT and DDLT.

OBJECTIVE

Provide an overview of biliary complications among LDLT and DDLT.

RESULTS

The incidence of biliary complications is higher among LDLT (28.7%) when compared with DDLT (15.5%). Bile leaks were the most common complication due to LDLT (17.1%); however, stricture was the most common complication due to DDLT (7.5%).

Selection of live-related liver transplantation candidates

PURPOSE

Living donor liver transplantation (LR) is an important alternative for children. We compared our outcomes of LR and cadaveric (CAD) graft recipients, with attention to the pediatric end-stage liver disease (PELD) score and perioperative morbidity and mortality to identify appropriate candidates for LR.

METHODS

Our transplant database and electronic medical records were searched for demographics and outcome measures.

RESULTS

From 2000 to 2008, 81 children underwent liver transplantation from 37 LR and 44 CAD donors. There were no significant differences in graft or overall survival at 3 months or 1 year. The LR group was significantly younger (4.46 +/- 5.2 years vs 7.41 +/- 6.6 years; P = .03) and had a significantly lower PELD score (12.7 +/- 13 vs 22 +/- 12; P = .001) at the time of transplantation. Ten patients were transplanted for unresectable tumor in the LR group vs 4 CAD (P = .03). Significantly fewer LR recipients required return to the operating room in the first 30 days posttransplant (13.9% vs 34.1%; P = .03). The LR recipients had a higher rate of biliary stricture requiring reoperation (22.2% vs 2.3%; P = .005).

CONCLUSIONS

The LR liver transplantation is highly selected for patients with a parent donor who will need transplant but do not yet have a high PELD score. A lower PELD score at operation may have contributed to the lower incidence of postoperative complications requiring reoperation.

Checklist: passport, plane ticket, organ transplant

Recently, active and proposed US medical insurance programs are taking steps to address the problems of organ availability, long waiting times, and high medical and surgical costs by promoting transplant tourism. Such programs are created explicitly to encourage policy holders to travel to a foreign country for the purpose of obtaining a transplant. Some medical insurance programs have gone as far as to bundle exotic travel and healthcare-transplantation not excluded-into one package. This article details some of the safety and ethics issues with these programs.

Barriers preventing liver transplantation in Canadians with HIV-infection--perceptions of HIV specialists

Liver transplantation is a life-saving procedure with demonstrated utility. There are accumulating data indicating that this procedure is helpful in HIV-infected patients as well. Liver transplantation is currently largely unavailable to those living with HIV in Canada. Understanding the obstacles to this procedure is the first step to increasing access. Between August 2005 and November 2005, HIV physicians, one from each Canadian HIV Trials Network site, were asked to complete a quantitative questionnaire on adult liver transplant access and need. Forty-six per cent (16 of 35) of sites responded. A median 20% of the nearly 12,700 HIV patients followed at these sites had concurrent liver disease (20% caused by hepatitis C virus, 5% caused by hepatitis B virus and 5% were alcohol-related). On average, two patients per site were thought to be appropriate candidates for liver transplant evaluation. Eighty per cent of respondents anticipated increased need for liver transplantation over the next five years. Organ supply was universally identified as the chief obstacle to transplantation in patients with HIV. Other key issues included risk of hepatitis C virus reinfection and transplant surgical team willingness. Based on these data, it is believed that these issues should be the focus of efforts designed to increase access to transplantation in Canadians with end-stage liver disease and concurrent HIV.