Utility of pre-procurement bedside liver biopsy in the deceased extended-criteria liver donor

A contemporary analysis of 20,086 deceased donor liver biopsies

BACKGROUND

Pre-transplant deceased donor liver biopsy may impact decision making; however, interpretation of the results remains variable and depends on accepting center practice patterns.

METHODS

In this cohort study, adult recipients from 04/01/2015-12/31/2020 were identified using the UNOS STARfile data. The deceased donor liver biopsies were stratified by risk based on degree of fibrosis, macrovesicular fat content, and level of portal infiltration (low-risk: no fibrosis, no portal infiltrates, and <30% macrosteatosis; moderate-risk: some fibrosis or mild infiltrates and <30% macrosteatosis; high-risk: most fibrosis, moderate/marked infiltrates, or ≥30% macrosteatosis). Graft utilization, donor risk profile, and recipient outcomes were compared across groups.

RESULTS

Of the 51,094 donor livers available, 20,086 (39.3%) were biopsied, and 34,606 (67.7%) were transplanted. Of the transplanted livers, 14,908 (43.1%) were biopsied. The transplanted grafts had lower mean macrovesicular fat content (9.3% transplanted vs. 26.9% non-transplanted, P < 0.001) and less often had any degree of fibrosis (20.9% vs. 39.9%, P < 0.001) or portal infiltration (51.3% vs. 58.2%, P < 0.001) versus non-transplanted grafts. Post-transplant recipient LOS (14.2 days high-risk vs. 15.2 days low-risk, P = 0.170) and 1-year graft survival (90.5% vs. 91.7%, P = 0.137) did not differ significantly between high- versus low-risk groups. Kaplan-Meier survival estimates further revealed no differences in the 5-year graft survival across risk strata (P = 0.833). Of the 5178 grafts biopsied and turned down, PSM revealed 1338 (26.0%) were potentially useable based on biopsy results and donor characteristics.

CONCLUSION

Carefully matched deceased donor livers with some fibrosis, inflammation, or steatosis ≥30% may be suitable for transplantation. Further study of this group of grafts may decrease turndowns of potentially useable organs.

Non-invasive evaluation of hepatic macrosteatosis in deceased donors

INTRODUCTION

Liver allocation changes have led to increased travel and expenditures, highlighting the need to efficiently identify marginal livers suitable for transplant. We evaluated the validity of existing non-invasive liver quality tests and a novel machine learning-based model at predicting deceased donor macrosteatosis >30%.

METHODS

We compared previously-validated non-invasive tests and a novel machine learning-based model to biopsies in predicting macrosteatosis >30%. We also tested them in populations enriched for macrosteatosis.

RESULTS

The Hepatic Steatosis Index area-under-the-curve (AUC) was 0.56. At the threshold identified by Youden's J statistic, sensitivity, specificity, positive, and negative predictive values were 49.6%, 58.9%, 14.0%, and 89.7%. Other tests demonstrated comparable results. Machine learning produced the highest AUC (0.71). Even in populations enriched for macrosteatosis, no test was sufficiently predictive.

CONCLUSION

Commonly used clinical scoring systems and a novel machine learning-based model were not clinically useful, highlighting the importance of pre-procurement biopsies to facilitate allocation.

Impact of donor preprocurement cardiac arrest on clinical outcomes in pediatric deceased donor liver transplantation

PPCA has historically been considered detrimental to donor quality in LT, but transplantation of grafts from this group of donors is now routine. Our study aims to evaluate the outcomes associated with use of donors with a history of PPCA in the pediatric population. This study is a single-center retrospective analysis of all pediatric LTs performed over an 18-year period. Donors and recipients were stratified by the presence and length of donor PPCA time. Preprocurement donor and post-transplant recipient laboratory values were collected to assess the degree of ischemic liver injury associated with each donor group. Cox regression analysis was used to compare survival. The records for 130 deceased pediatric LT donors and corresponding recipients were reviewed. There were 73 (56%) non-PPCA donors and 57 (44%) PPCA donors. Donors that experienced a PPCA event demonstrated a higher median, pretransplant peak alanine aminotransferase (ALT) level (P < .001). When comparing post-transplant recipient median ALT levels, donors with any PPCA had lower median peak ALT (P = .15) and day 3 ALT (P = .43) levels than the non-PPCA group. Rates of early graft loss did not differ. The PPCA group with >40 minutes of ischemia had markedly lower survival at 10 years, but this finding did not reach statistical significance. Liver grafts from donors with or without PPCA demonstrated no statistically significant differences in function or survival. A history of donor PPCA alone should not be used as an exclusionary criterion in pediatric liver transplantation.

The role of deceased donor liver biopsy: An analysis of 5449 liver transplant recipients

BACKGROUND

No standard exists for the use of deceased donor liver biopsy during procurement. We sought to evaluate liver biopsy and the impact of findings on outcomes and graft utilization.

METHODS

A prospective observational study of donors after neurologic determination of death was conducted from 02/2012-08/2017 (16 OPOs). Donor data were collected through the UNOS Donor Management Goals Registry Web Portal and linked to the Scientific Registry of Transplant Recipients (SRTR) for recipient outcomes. Recipients of biopsied donor livers (BxDL) were studied and a Cox proportional hazard analysis was used to identify independent predictors of 1-year graft survival.

RESULTS

Data from 5449 liver transplant recipients were analyzed, of which 1791(33%) received a BxDL. There was no difference in graft or patient survival between the non-BxDL and BxDL recipient groups. On adjusted analysis of BxDL recipients, macrosteatosis (21%-30%[n = 148] and >30%[n = 92]) was not found to predict 1-year graft survival, whereas increasing donor age (HR1.02), donor Hispanic ethnicity (HR1.62), donor INR (HR1.18), and recipient life support (HR2.29) were.

CONCLUSIONS

Excellent graft and patient survival can be achieved in recipients of BxDL grafts. Notably, as demonstrated by the lack of effect of macrosteatosis on survival, donor to recipient matching may contribute to these outcomes.

Liver Transplantations and Brain Dead Donors With Alcohol Abuse

BACKGROUND AND AIM

Liver grafts from donors with chronic and active history of alcohol abuse are usually immediately ruled out for use in liver transplantation (LT). The aim of our study is to evaluate the use of those grafts.

METHODS

From 2011 to 2016, a study group (Group 1) composed of 5 adult LT patients transplanted with livers from donors with alcohol abuse, was compared with a control group (Group 2) of 10 randomly matched patients who received liver transplants. Preoperative, intraoperative, and postoperative data were compared.

RESULTS

Among donors, serum gamma-glutamyl transferase values were significantly higher in Group 1. In recipients, post-LT laboratory exams showed significantly higher peak values of aspartate transaminase and alanine transaminase in Group 1; higher values of aspartate aminotransferase, alanine aminotransferase, and total bilirubin in Group 1 were also recorded on day 0. Early allograft dysfunction occurred at higher rates in Group 1 (80% vs 20%, P = .025), with no differences in early rejection episodes or early surgical repeat interventions. All patients from both groups were alive after 20 ± 10 (range 6-35) months from LT.

CONCLUSION

Despite higher rates of early allograft dysfunction, selected liver grafts from donors with alcohol abuse can be accepted for LT with good clinical results.

Impact of Donor Pre-Procurement Cardiac Arrest (PPCA) on Clinical Outcomes in Liver Transplantation

Background

Transplantation of liver grafts from deceased donors who experienced cardiac arrest prior to liver procurement is now common. This single-center study analyzed the impact of pre-donation arrest time on clinical outcomes in liver transplantation.

Material/Methods

Records of all orthotopic liver transplants performed at a single center over a 15-year period were reviewed. Donor records were reviewed and total arrest time was calculated as cumulative minutes. Post-transplant liver graft function was assessed using laboratory values. Graft survival was assessed with Cox regression analysis.

Results

Records for 1830 deceased donor transplants were reviewed, and 521 donors experienced pre-procurement cardiac arrest (28%). Median arrest time was 21 min (mean 25 min, range 1–120 min). After transplant, the peak alanine aminotransferase and bilirubin levels for liver grafts from donors with arrest were lower compared to those for donors without arrest (p<0.001). Early allograft dysfunction occurred in 25% (arrest) and 28% (no arrest) of patients (p=0.22). There were no differences in risk of early graft loss (3% vs. 3%, p=0.84), length of hospital stay (10 vs. 10 days, p=0.76), and 1-year graft survival (89% vs. 89%, p=0.94). Cox regression analysis comparing 4 groups (no arrest, <20 min, 20–40 min, and >40 min arrest) demonstrated no statistically significant difference in survival at 10 years. Subgroup analysis of 93 donation after cardiac death grafts showed no significant difference for these same outcomes.

Conclusions

These results support the use of select deceased liver donors who experience pre-donation cardiac arrest. Pre-donation arrest may be associated with less early allograft dysfunction, but had no impact on long-term clinical outcomes. The results for donation after cardiac death donors were similar.

Challenges and future developments in liver transplantation

Liver transplantation (LT) has become the treatment of choice for a wide range of liver diseases in both adult and pediatric patients. Until recently, the largest proportion of LT in adults, were performed in patients with hepatitis C (HCV) related cirrhosis. The recent availability of safe and effective direct antiviral agents to cure HCV infection in almost all patients whatever the HCV genotype and severity of liver disease, will reduce the need for LT in this category of recipients. Thus, it is presumed that in the next 1 to 2 decades HCV related liver disease will diminish substantially, whereas non-alcoholic steato-hepatitis (NASH) will correspondingly escalate as an indication for LT. The greatest challenges facing LT remain the limited supply of donor organs, and the need for chronic immunosuppression, which represent the true obstacles to the greater application and durable success of the LT procedure. This review aimed to highlight, in different sections, the main open issues and future developments in LT. These will be focused to explore current and future strategies to maximize the use of limited organs, to offer an update on potential new approaches to immunosuppression and to imagine new indications for LT when the number of patients awaiting transplants for HCV related liver disease is reduced.

Liver biopsy in assessment of extended criteria donors

The safety and liver utilization with prerecovery liver biopsy (PLB) in extended criteria liver donors are unclear. We conducted a retrospective cohort study in 1323 brain death donors (PLB = 496) from 3 organ procurement organizations (OPOs). Outcomes were complications, preempted liver recovery (PLR), and liver transplantation (LT). Additional analyses included liver-only and propensity score-matched multiorgan donor subgroups. PLB donors were older (57 versus 53 years; P < 0.001). Hepatitis C antibody positivity (14.3% versus 9.6%, P = 0.01) and liver-only donors (42.6% versus 17.5%; P < 0.001) were more prevalent. The PLB cohort had fewer complications (31.9% versus 42.3%; P < 0.001). In the PLB cohort, PLR was significantly higher (odds ratio [OR], 3.45; 95% confidence interval [CI], 2.42-4.92) and LT lower (OR, 0.69; 95% CI, 0.52-0.91). In liver-only and propensity score-matched multiorgan donor subgroups, PLR was significantly higher (OR, 1.76; 95% CI, 1.06-2.94 and OR, 2.29; 95% CI, 1.37-3.82, respectively) without a decrease in LT (OR, 0.71; 95% CI, 0.43-1.18 and OR, 0.91; 95% CI, 0.63-1.33, respectively) in PLB subgroups. In conclusion, in extended criteria liver donors, PLB is safe and decreases futile liver recovery without decreasing LT. Increased use of PLB, especially in liver-only donors, is likely to save costs to OPOs and transplant centers and improve efficiencies in organ allocation. Liver Transplantation 24 182-191 2018 AASLD.

Sent Liver Grafts Do Not Have a Detrimental Impact on Post-transplant Outcome

INTRODUCTION

"Sent livers" (SL) (interregional allocated organs) are considered extended donor criteria grafts. These grafts influence post-transplant outcome. In our donor allocation program, the number of allocated SLs is increasing. The aim of our study is to provide data supporting the possibility to enlarge the use of SLs through adequate donor-to-recipient matching.

METHODS

A retrospective analysis was carried out from our prospective-collected database during 2014.

RESULTS

Fifty-seven liver transplantations (LTs) were included: 22 SLs and 35 grafts procured by us (nSLs). Only donor risk index among donor characteristics showed a trend toward significant values (SL 1.901 vs nSL 1.726, P = .07). Among LT variables, the number of patients who received interleukin-2 inhibitor induction (SL 7 vs nSL 20, P < .05) and the presence of hepatocellular carcinoma (SL 50% vs nSL 34%, P < .05) reached statistical significance. One case of primary nonfunction occurred in the nSL group. No major retrieval injuries were observed. Retransplantation was performed in 6 cases (2 SLs and 4 nSLs). One patient in the SL group died after retransplantation. Graft survival rates at 1, 3, 6, and 12 months were 100%, 100%, 90%, 86% and 91%, 86%, 86%, 86% (P = .79) in SL and nSL groups, respectively.

DISCUSSION

SL performance did not differ from that of nSL. SLs were usually allocated to noncritical candidates, and nSLs were transplanted more frequently in decompensated recipients. Despite this peculiar donor-recipient match, grafts survival was similar in the 2 groups of patients.

Strategies to optimize the use of marginal donors in liver transplantation

Liver transplantation is the treatment of choice for end stage liver disease, but availability of liver grafts is still the main limitation to its wider use. Extended criteria donors (ECD) are considered not ideal for several reasons but their use has dramatically grown in the last decades in order to augment the donor liver pool. Due to improvement in surgical and medical strategies, results using grafts from these donors have become acceptable in terms of survival and complications; nevertheless a big debate still exists regarding their selection, discharge criteria and allocation policies. Many studies analyzed the use of these grafts from many points of view producing different or contradictory results so that accepted guidelines do not exist and the use of these grafts is still related to non-standardized policies changing from center to center. The aim of this review is to analyze every step of the donation-transplantation process emphasizing all those strategies, both clinical and experimental, that can optimize results using ECD.